/*----------------------------------------------------------------------------/
 /  FatFs - FAT file system module  R0.09b                 (C)ChaN, 2013
 /-----------------------------------------------------------------------------/
 / FatFs module is a generic FAT file system module for small embedded systems.
 / This is a free software that opened for education, research and commercial
 / developments under license policy of following terms.
 /
 /  Copyright (C) 2013, ChaN, all right reserved.
 /
 / * The FatFs module is a free software and there is NO WARRANTY.
 / * No restriction on use. You can use, modify and redistribute it for
 /   personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
 / * Redistributions of source code must retain the above copyright notice.
 /
 /-----------------------------------------------------------------------------/
 / Feb 26,'06 R0.00  Prototype.
 /
 / Apr 29,'06 R0.01  First stable version.
 /
 / Jun 01,'06 R0.02  Added FAT12 support.
 /                   Removed unbuffered mode.
 /                   Fixed a problem on small (<32M) partition.
 / Jun 10,'06 R0.02a Added a configuration option (_FS_MINIMUM).
 /
 / Sep 22,'06 R0.03  Added f_rename().
 /                   Changed option _FS_MINIMUM to _FS_MINIMIZE.
 / Dec 11,'06 R0.03a Improved cluster scan algorithm to write files fast.
 /                   Fixed f_mkdir() creates incorrect directory on FAT32.
 /
 / Feb 04,'07 R0.04  Supported multiple drive system.
 /                   Changed some interfaces for multiple drive system.
 /                   Changed f_mountdrv() to f_mount().
 /                   Added f_mkfs().
 / Apr 01,'07 R0.04a Supported multiple partitions on a physical drive.
 /                   Added a capability of extending file size to f_lseek().
 /                   Added minimization level 3.
 /                   Fixed an endian sensitive code in f_mkfs().
 / May 05,'07 R0.04b Added a configuration option _USE_NTFLAG.
 /                   Added FSInfo support.
 /                   Fixed DBCS name can result FR_INVALID_NAME.
 /                   Fixed short seek (<= csize) collapses the file object.
 /
 / Aug 25,'07 R0.05  Changed arguments of f_read(), f_write() and f_mkfs().
 /                   Fixed f_mkfs() on FAT32 creates incorrect FSInfo.
 /                   Fixed f_mkdir() on FAT32 creates incorrect directory.
 / Feb 03,'08 R0.05a Added f_truncate() and f_utime().
 /                   Fixed off by one error at FAT sub-type determination.
 /                   Fixed btr in f_read() can be mistruncated.
 /                   Fixed cached sector is not flushed when create and close without write.
 /
 / Apr 01,'08 R0.06  Added fputc(), fputs(), fprintf() and fgets().
 /                   Improved performance of f_lseek() on moving to the same or following cluster.
 /
 / Apr 01,'09 R0.07  Merged Tiny-FatFs as a configuration option. (_FS_TINY)
 /                   Added long file name feature.
 /                   Added multiple code page feature.
 /                   Added re-entrancy for multitask operation.
 /                   Added auto cluster size selection to f_mkfs().
 /                   Added rewind option to f_readdir().
 /                   Changed result code of critical errors.
 /                   Renamed string functions to avoid name collision.
 / Apr 14,'09 R0.07a Separated out OS dependent code on reentrant cfg.
 /                   Added multiple sector size feature.
 / Jun 21,'09 R0.07c Fixed f_unlink() can return FR_OK on error.
 /                   Fixed wrong cache control in f_lseek().
 /                   Added relative path feature.
 /                   Added f_chdir() and f_chdrive().
 /                   Added proper case conversion to extended char.
 / Nov 03,'09 R0.07e Separated out configuration options from ff.h to ffconf.h.
 /                   Fixed f_unlink() fails to remove a sub-dir on _FS_RPATH.
 /                   Fixed name matching error on the 13 char boundary.
 /                   Added a configuration option, _LFN_UNICODE.
 /                   Changed f_readdir() to return the SFN with always upper case on non-LFN cfg.
 /
 / May 15,'10 R0.08  Added a memory configuration option. (_USE_LFN = 3)
 /                   Added file lock feature. (_FS_SHARE)
 /                   Added fast seek feature. (_USE_FASTSEEK)
 /                   Changed some types on the API, XCHAR->TCHAR.
 /                   Changed fname member in the FILINFO structure on Unicode cfg.
 /                   String functions support UTF-8 encoding files on Unicode cfg.
 / Aug 16,'10 R0.08a Added f_getcwd(). (_FS_RPATH = 2)
 /                   Added sector erase feature. (_USE_ERASE)
 /                   Moved file lock semaphore table from fs object to the bss.
 /                   Fixed a wrong directory entry is created on non-LFN cfg when the given name contains ';'.
 /                   Fixed f_mkfs() creates wrong FAT32 volume.
 / Jan 15,'11 R0.08b Fast seek feature is also applied to f_read() and f_write().
 /                   f_lseek() reports required table size on creating CLMP.
 /                   Extended format syntax of f_printf function.
 /                   Ignores duplicated directory separators in given path name.
 /
 / Sep 06,'11 R0.09  f_mkfs() supports multiple partition to finish the multiple partition feature.
 /                   Added f_fdisk(). (_MULTI_PARTITION = 2)
 / Aug 27,'12 R0.09a Fixed assertion failure due to OS/2 EA on FAT12/16 volume.
 /                   Changed f_open() and f_opendir reject null object pointer to avoid crash.
 /                   Changed option name _FS_SHARE to _FS_LOCK.
 / Jan 24,'13 R0.09b Added f_setlabel() and f_getlabel(). (_USE_LABEL = 1)
 /---------------------------------------------------------------------------*/

#include "ff.h"			/* FatFs configurations and declarations */
#include "diskio.h"		/* Declarations of low level disk I/O functions */

/*--------------------------------------------------------------------------

 Module Private Definitions

 ---------------------------------------------------------------------------*/

#if _FATFS != 82786	/* Revision ID */
#error Wrong include file (ff.h).
#endif

/* Definitions on sector size */
#if _MAX_SS != 512 && _MAX_SS != 1024 && _MAX_SS != 2048 && _MAX_SS != 4096
#error Wrong sector size.
#endif
#if _MAX_SS != 512
#define	SS(fs)	((fs)->ssize)	/* Variable sector size */
#else
#define	SS(fs)	512U			/* Fixed sector size */
#endif

/* Reentrancy related */
#if _FS_REENTRANT
#if _USE_LFN == 1
#error Static LFN work area must not be used in re-entrant configuration.
#endif
#define	ENTER_FF(fs)		{ if (!lock_fs(fs)) return FR_TIMEOUT; }
#define	LEAVE_FF(fs, res)	{ unlock_fs(fs, res); return res; }
#else
#define	ENTER_FF(fs)
#define LEAVE_FF(fs, res)	return res
#endif

#define	ABORT(fs, res)		{ fp->flag |= FA__ERROR; LEAVE_FF(fs, res); }

/* File access control feature */
#if _FS_LOCK
#if _FS_READONLY
#error _FS_LOCK must be 0 on read-only cfg.
#endif
typedef struct {
    FATFS *fs; /* File ID 1, volume (NULL:blank entry) */
    DWORD clu; /* File ID 2, directory */
    WORD idx; /* File ID 3, directory index */
    WORD ctr; /* File open counter, 0:none, 0x01..0xFF:read open count, 0x100:write mode */
}FILESEM;
#endif

/* DBCS code ranges and SBCS extend char conversion table */

#if _CODE_PAGE == 932	/* Japanese Shift-JIS */
#define _DF1S	0x81	/* DBC 1st byte range 1 start */
#define _DF1E	0x9F	/* DBC 1st byte range 1 end */
#define _DF2S	0xE0	/* DBC 1st byte range 2 start */
#define _DF2E	0xFC	/* DBC 1st byte range 2 end */
#define _DS1S	0x40	/* DBC 2nd byte range 1 start */
#define _DS1E	0x7E	/* DBC 2nd byte range 1 end */
#define _DS2S	0x80	/* DBC 2nd byte range 2 start */
#define _DS2E	0xFC	/* DBC 2nd byte range 2 end */

#elif _CODE_PAGE == 936	/* Simplified Chinese GBK */
#define _DF1S	0x81
#define _DF1E	0xFE
#define _DS1S	0x40
#define _DS1E	0x7E
#define _DS2S	0x80
#define _DS2E	0xFE

#elif _CODE_PAGE == 949	/* Korean */
#define _DF1S	0x81
#define _DF1E	0xFE
#define _DS1S	0x41
#define _DS1E	0x5A
#define _DS2S	0x61
#define _DS2E	0x7A
#define _DS3S	0x81
#define _DS3E	0xFE

#elif _CODE_PAGE == 950	/* Traditional Chinese Big5 */
#define _DF1S	0x81
#define _DF1E	0xFE
#define _DS1S	0x40
#define _DS1E	0x7E
#define _DS2S	0xA1
#define _DS2E	0xFE

#elif _CODE_PAGE == 437	/* U.S. (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x90,0x41,0x8E,0x41,0x8F,0x80,0x45,0x45,0x45,0x49,0x49,0x49,0x8E,0x8F,0x90,0x92,0x92,0x4F,0x99,0x4F,0x55,0x55,0x59,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0x41,0x49,0x4F,0x55,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 720	/* Arabic (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x45,0x41,0x84,0x41,0x86,0x43,0x45,0x45,0x45,0x49,0x49,0x8D,0x8E,0x8F,0x90,0x92,0x92,0x93,0x94,0x95,0x49,0x49,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 737	/* Greek (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x92,0x92,0x93,0x94,0x95,0x96,0x97,0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87, \
				0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0xAA,0x92,0x93,0x94,0x95,0x96,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0x97,0xEA,0xEB,0xEC,0xE4,0xED,0xEE,0xE7,0xE8,0xF1,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 775	/* Baltic (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x91,0xA0,0x8E,0x95,0x8F,0x80,0xAD,0xED,0x8A,0x8A,0xA1,0x8D,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0x95,0x96,0x97,0x97,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xE0,0xA3,0xA3,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xB5,0xB6,0xB7,0xB8,0xBD,0xBE,0xC6,0xC7,0xA5,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE3,0xE8,0xE8,0xEA,0xEA,0xEE,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 850	/* Multilingual Latin 1 (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0xDE,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x59,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
				0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE7,0xE9,0xEA,0xEB,0xED,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 852	/* Latin 2 (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xDE,0x8F,0x80,0x9D,0xD3,0x8A,0x8A,0xD7,0x8D,0x8E,0x8F,0x90,0x91,0x91,0xE2,0x99,0x95,0x95,0x97,0x97,0x99,0x9A,0x9B,0x9B,0x9D,0x9E,0x9F, \
				0xB5,0xD6,0xE0,0xE9,0xA4,0xA4,0xA6,0xA6,0xA8,0xA8,0xAA,0x8D,0xAC,0xB8,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBD,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC6,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD2,0xD3,0xD2,0xD5,0xD6,0xD7,0xB7,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE3,0xD5,0xE6,0xE6,0xE8,0xE9,0xE8,0xEB,0xED,0xED,0xDD,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xEB,0xFC,0xFC,0xFE,0xFF}

#elif _CODE_PAGE == 855	/* Cyrillic (OEM) */
#define _DF1S	0
#define _EXCVT {0x81,0x81,0x83,0x83,0x85,0x85,0x87,0x87,0x89,0x89,0x8B,0x8B,0x8D,0x8D,0x8F,0x8F,0x91,0x91,0x93,0x93,0x95,0x95,0x97,0x97,0x99,0x99,0x9B,0x9B,0x9D,0x9D,0x9F,0x9F, \
				0xA1,0xA1,0xA3,0xA3,0xA5,0xA5,0xA7,0xA7,0xA9,0xA9,0xAB,0xAB,0xAD,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB6,0xB6,0xB8,0xB8,0xB9,0xBA,0xBB,0xBC,0xBE,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD3,0xD3,0xD5,0xD5,0xD7,0xD7,0xDD,0xD9,0xDA,0xDB,0xDC,0xDD,0xE0,0xDF, \
				0xE0,0xE2,0xE2,0xE4,0xE4,0xE6,0xE6,0xE8,0xE8,0xEA,0xEA,0xEC,0xEC,0xEE,0xEE,0xEF,0xF0,0xF2,0xF2,0xF4,0xF4,0xF6,0xF6,0xF8,0xF8,0xFA,0xFA,0xFC,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 857	/* Turkish (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0x98,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x98,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9E, \
				0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA6,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xDE,0x59,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 858	/* Multilingual Latin 1 + Euro (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0xDE,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x59,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
				0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE7,0xE9,0xEA,0xEB,0xED,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 862	/* Hebrew (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0x41,0x49,0x4F,0x55,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 866	/* Russian (OEM) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0x90,0x91,0x92,0x93,0x9d,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F,0xF0,0xF0,0xF2,0xF2,0xF4,0xF4,0xF6,0xF6,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 874	/* Thai (OEM, Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1250 /* Central Europe (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x8D,0x8E,0x8F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xA3,0xB4,0xB5,0xB6,0xB7,0xB8,0xA5,0xAA,0xBB,0xBC,0xBD,0xBC,0xAF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xFF}

#elif _CODE_PAGE == 1251 /* Cyrillic (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x82,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x80,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x8D,0x8E,0x8F, \
				0xA0,0xA2,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB2,0xA5,0xB5,0xB6,0xB7,0xA8,0xB9,0xAA,0xBB,0xA3,0xBD,0xBD,0xAF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF}

#elif _CODE_PAGE == 1252 /* Latin 1 (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0xAd,0x9B,0x8C,0x9D,0xAE,0x9F, \
				0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0x9F}

#elif _CODE_PAGE == 1253 /* Greek (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xA2,0xB8,0xB9,0xBA, \
				0xE0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xF2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xFB,0xBC,0xFD,0xBF,0xFF}

#elif _CODE_PAGE == 1254 /* Turkish (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x9D,0x9E,0x9F, \
				0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0x9F}

#elif _CODE_PAGE == 1255 /* Hebrew (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1256 /* Arabic (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x8C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0x41,0xE1,0x41,0xE3,0xE4,0xE5,0xE6,0x43,0x45,0x45,0x45,0x45,0xEC,0xED,0x49,0x49,0xF0,0xF1,0xF2,0xF3,0x4F,0xF5,0xF6,0xF7,0xF8,0x55,0xFA,0x55,0x55,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1257 /* Baltic (Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
				0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xA8,0xB9,0xAA,0xBB,0xBC,0xBD,0xBE,0xAF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xFF}

#elif _CODE_PAGE == 1258 /* Vietnam (OEM, Windows) */
#define _DF1S	0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0xAC,0x9D,0x9E,0x9F, \
				0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
				0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xEC,0xCD,0xCE,0xCF,0xD0,0xD1,0xF2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xFE,0x9F}

#elif _CODE_PAGE == 1	/* ASCII (for only non-LFN cfg) */
#if _USE_LFN
#error Cannot use LFN feature without valid code page.
#endif
#define _DF1S	0

#else
#error Unknown code page

#endif

/* Character code support macros */
#define IsUpper(c)	(((c)>='A')&&((c)<='Z'))
#define IsLower(c)	(((c)>='a')&&((c)<='z'))
#define IsDigit(c)	(((c)>='0')&&((c)<='9'))

#if _DF1S		/* Code page is DBCS */

#ifdef _DF2S	/* Two 1st byte areas */
#define IsDBCS1(c)	(((BYTE)(c) >= _DF1S && (BYTE)(c) <= _DF1E) || ((BYTE)(c) >= _DF2S && (BYTE)(c) <= _DF2E))
#else			/* One 1st byte area */
#define IsDBCS1(c)	((BYTE)(c) >= _DF1S && (BYTE)(c) <= _DF1E)
#endif

#ifdef _DS3S	/* Three 2nd byte areas */
#define IsDBCS2(c)	(((BYTE)(c) >= _DS1S && (BYTE)(c) <= _DS1E) || ((BYTE)(c) >= _DS2S && (BYTE)(c) <= _DS2E) || ((BYTE)(c) >= _DS3S && (BYTE)(c) <= _DS3E))
#else			/* Two 2nd byte areas */
#define IsDBCS2(c)	(((BYTE)(c) >= _DS1S && (BYTE)(c) <= _DS1E) || ((BYTE)(c) >= _DS2S && (BYTE)(c) <= _DS2E))
#endif

#else			/* Code page is SBCS */

#define IsDBCS1(c)	0
#define IsDBCS2(c)	0

#endif /* _DF1S */

/* Name status flags */
#define NS			11		/* Index of name status byte in fn[] */
#define NS_LOSS		0x01	/* Out of 8.3 format */
#define NS_LFN		0x02	/* Force to create LFN entry */
#define NS_LAST		0x04	/* Last segment */
#define NS_BODY		0x08	/* Lower case flag (body) */
#define NS_EXT		0x10	/* Lower case flag (ext) */
#define NS_DOT		0x20	/* Dot entry */

/* FAT sub-type boundaries */
/* Note that the FAT spec by Microsoft says 4085 but Windows works with 4087! */
#define MIN_FAT16	4086	/* Minimum number of clusters for FAT16 */
#define	MIN_FAT32	65526	/* Minimum number of clusters for FAT32 */

/* FatFs refers the members in the FAT structures as byte array instead of
 / structure member because the structure is not binary compatible between
 / different platforms */

#define BS_jmpBoot			0	/* Jump instruction (3) */
#define BS_OEMName			3	/* OEM name (8) */
#define BPB_BytsPerSec		11	/* Sector size [byte] (2) */
#define BPB_SecPerClus		13	/* Cluster size [sector] (1) */
#define BPB_RsvdSecCnt		14	/* Size of reserved area [sector] (2) */
#define BPB_NumFATs			16	/* Number of FAT copies (1) */
#define BPB_RootEntCnt		17	/* Number of root dir entries for FAT12/16 (2) */
#define BPB_TotSec16		19	/* Volume size [sector] (2) */
#define BPB_Media			21	/* Media descriptor (1) */
#define BPB_FATSz16			22	/* FAT size [sector] (2) */
#define BPB_SecPerTrk		24	/* Track size [sector] (2) */
#define BPB_NumHeads		26	/* Number of heads (2) */
#define BPB_HiddSec			28	/* Number of special hidden sectors (4) */
#define BPB_TotSec32		32	/* Volume size [sector] (4) */
#define BS_DrvNum			36	/* Physical drive number (2) */
#define BS_BootSig			38	/* Extended boot signature (1) */
#define BS_VolID			39	/* Volume serial number (4) */
#define BS_VolLab			43	/* Volume label (8) */
#define BS_FilSysType		54	/* File system type (1) */
#define BPB_FATSz32			36	/* FAT size [sector] (4) */
#define BPB_ExtFlags		40	/* Extended flags (2) */
#define BPB_FSVer			42	/* File system version (2) */
#define BPB_RootClus		44	/* Root dir first cluster (4) */
#define BPB_FSInfo			48	/* Offset of FSInfo sector (2) */
#define BPB_BkBootSec		50	/* Offset of backup boot sector (2) */
#define BS_DrvNum32			64	/* Physical drive number (2) */
#define BS_BootSig32		66	/* Extended boot signature (1) */
#define BS_VolID32			67	/* Volume serial number (4) */
#define BS_VolLab32			71	/* Volume label (8) */
#define BS_FilSysType32		82	/* File system type (1) */
#define	FSI_LeadSig			0	/* FSI: Leading signature (4) */
#define	FSI_StrucSig		484	/* FSI: Structure signature (4) */
#define	FSI_Free_Count		488	/* FSI: Number of free clusters (4) */
#define	FSI_Nxt_Free		492	/* FSI: Last allocated cluster (4) */
#define MBR_Table			446	/* MBR: Partition table offset (2) */
#define	SZ_PTE				16	/* MBR: Size of a partition table entry */
#define BS_55AA				510	/* Boot sector signature (2) */

#define	DIR_Name			0	/* Short file name (11) */
#define	DIR_Attr			11	/* Attribute (1) */
#define	DIR_NTres			12	/* NT flag (1) */
#define DIR_CrtTimeTenth	13	/* Created time sub-second (1) */
#define	DIR_CrtTime			14	/* Created time (2) */
#define	DIR_CrtDate			16	/* Created date (2) */
#define DIR_LstAccDate		18	/* Last accessed date (2) */
#define	DIR_FstClusHI		20	/* Higher 16-bit of first cluster (2) */
#define	DIR_WrtTime			22	/* Modified time (2) */
#define	DIR_WrtDate			24	/* Modified date (2) */
#define	DIR_FstClusLO		26	/* Lower 16-bit of first cluster (2) */
#define	DIR_FileSize		28	/* File size (4) */
#define	LDIR_Ord			0	/* LFN entry order and LLE flag (1) */
#define	LDIR_Attr			11	/* LFN attribute (1) */
#define	LDIR_Type			12	/* LFN type (1) */
#define	LDIR_Chksum			13	/* Sum of corresponding SFN entry */
#define	LDIR_FstClusLO		26	/* Filled by zero (0) */
#define	SZ_DIR				32		/* Size of a directory entry */
#define	LLE					0x40	/* Last long entry flag in LDIR_Ord */
#define	DDE					0xE5	/* Deleted directory entry mark in DIR_Name[0] */
#define	NDDE				0x05	/* Replacement of the character collides with DDE */

/*------------------------------------------------------------*/
/* Module private work area                                   */
/*------------------------------------------------------------*/
/* Note that uninitialized variables with static duration are
 /  zeroed/nulled at start-up. If not, the compiler or start-up
 /  routine is out of ANSI-C standard.
 */

#if _VOLUMES
static FATFS *FatFs[_VOLUMES]; /* Pointer to the file system objects (logical drives) */
#else
#error Number of volumes must not be 0.
#endif

static WORD Fsid; /* File system mount ID */

#if _FS_RPATH
static
BYTE CurrVol; /* Current drive */
#endif

#if _FS_LOCK
static
FILESEM Files[_FS_LOCK]; /* File lock semaphores */
#endif

#if _USE_LFN == 0			/* No LFN feature */
#define	DEF_NAMEBUF			BYTE sfn[12]
#define INIT_BUF(dobj)		(dobj).fn = sfn
#define	FREE_BUF()

#elif _USE_LFN == 1			/* LFN feature with static working buffer */
static WCHAR LfnBuf[_MAX_LFN + 1];
#define	DEF_NAMEBUF			BYTE sfn[12]
#define INIT_BUF(dobj)		{ (dobj).fn = sfn; (dobj).lfn = LfnBuf; }
#define	FREE_BUF()

#elif _USE_LFN == 2 		/* LFN feature with dynamic working buffer on the stack */
#define	DEF_NAMEBUF			BYTE sfn[12]; WCHAR lbuf[_MAX_LFN+1]
#define INIT_BUF(dobj)		{ (dobj).fn = sfn; (dobj).lfn = lbuf; }
#define	FREE_BUF()

#elif _USE_LFN == 3 		/* LFN feature with dynamic working buffer on the heap */
#define	DEF_NAMEBUF			BYTE sfn[12]; WCHAR *lfn
#define INIT_BUF(dobj)		{ lfn = ff_memalloc((_MAX_LFN + 1) * 2); \
							  if (!lfn) LEAVE_FF((dobj).fs, FR_NOT_ENOUGH_CORE); \
							  (dobj).lfn = lfn;	(dobj).fn = sfn; }
#define	FREE_BUF()			ff_memfree(lfn)

#else
#error Wrong LFN configuration.
#endif

#ifdef _EXCVT
static const BYTE ExCvt[] = _EXCVT; /* Upper conversion table for extended chars */
#endif

/*--------------------------------------------------------------------------

 Module Private Functions

 ---------------------------------------------------------------------------*/

/*-----------------------------------------------------------------------*/
/* String functions                                                      */
/*-----------------------------------------------------------------------*/

/* Copy memory to memory */
static
void mem_cpy(void* dst, const void* src, UINT cnt) {
    BYTE *d = (BYTE*) dst;
    const BYTE *s = (const BYTE*) src;

#if _WORD_ACCESS == 1
    while (cnt >= sizeof (int)) {
        *(int*)d = *(int*)s;
        d += sizeof (int); s += sizeof (int);
        cnt -= sizeof (int);
    }
#endif
    while (cnt--)
        *d++ = *s++;
}

/* Fill memory */
static
void mem_set(void* dst, int val, UINT cnt) {
    BYTE *d = (BYTE*) dst;

    while (cnt--)
        *d++ = (BYTE) val;
}

/* Compare memory to memory */
static
int mem_cmp(const void* dst, const void* src, UINT cnt) {
    const BYTE *d = (const BYTE *) dst, *s = (const BYTE *) src;
    int r = 0;

    while (cnt-- && (r = *d++ - *s++) == 0)
        ;
    return r;
}

/* Check if chr is contained in the string */
static
int chk_chr(const char* str, int chr) {
    while (*str && *str != chr)
        str++;
    return *str;
}

/*-----------------------------------------------------------------------*/
/* Request/Release grant to access the volume                            */
/*-----------------------------------------------------------------------*/
#if _FS_REENTRANT

static
int lock_fs (
        FATFS *fs /* File system object */
)
{
    return ff_req_grant(fs->sobj);
}

static
void unlock_fs (
        FATFS *fs, /* File system object */
        FRESULT res /* Result code to be returned */
)
{
    if (fs &&
            res != FR_NOT_ENABLED &&
            res != FR_INVALID_DRIVE &&
            res != FR_INVALID_OBJECT &&
            res != FR_TIMEOUT) {
        ff_rel_grant(fs->sobj);
    }
}
#endif

/*-----------------------------------------------------------------------*/
/* File lock control functions                                           */
/*-----------------------------------------------------------------------*/
#if _FS_LOCK

static
FRESULT chk_lock ( /* Check if the file can be accessed */
        DIR* dj, /* Directory object pointing the file to be checked */
        int acc /* Desired access (0:Read, 1:Write, 2:Delete/Rename) */
)
{
    UINT i, be;

    /* Search file semaphore table */
    for (i = be = 0; i < _FS_LOCK; i++) {
        if (Files[i].fs) { /* Existing entry */
            if (Files[i].fs == dj->fs && /* Check if the file matched with an open file */
                    Files[i].clu == dj->sclust &&
                    Files[i].idx == dj->index) break;
        } else { /* Blank entry */
            be++;
        }
    }
    if (i == _FS_LOCK) /* The file is not opened */
    return (be || acc == 2) ? FR_OK : FR_TOO_MANY_OPEN_FILES; /* Is there a blank entry for new file? */

    /* The file has been opened. Reject any open against writing file and all write mode open */
    return (acc || Files[i].ctr == 0x100) ? FR_LOCKED : FR_OK;
}

static
int enq_lock (void) /* Check if an entry is available for a new file */
{
    UINT i;

    for (i = 0; i < _FS_LOCK && Files[i].fs; i++);
    return (i == _FS_LOCK) ? 0 : 1;
}

static
UINT inc_lock ( /* Increment file open counter and returns its index (0:int error) */
        DIR* dj, /* Directory object pointing the file to register or increment */
        int acc /* Desired access mode (0:Read, !0:Write) */
)
{
    UINT i;

    for (i = 0; i < _FS_LOCK; i++) { /* Find the file */
        if (Files[i].fs == dj->fs &&
                Files[i].clu == dj->sclust &&
                Files[i].idx == dj->index) break;
    }

    if (i == _FS_LOCK) { /* Not opened. Register it as new. */
        for (i = 0; i < _FS_LOCK && Files[i].fs; i++);
        if (i == _FS_LOCK) return 0; /* No space to register (int err) */
        Files[i].fs = dj->fs;
        Files[i].clu = dj->sclust;
        Files[i].idx = dj->index;
        Files[i].ctr = 0;
    }

    if (acc && Files[i].ctr) return 0; /* Access violation (int err) */

    Files[i].ctr = acc ? 0x100 : Files[i].ctr + 1; /* Set semaphore value */

    return i + 1;
}

static
FRESULT dec_lock ( /* Decrement file open counter */
        UINT i /* Semaphore index */
)
{
    WORD n;
    FRESULT res;

    if (--i < _FS_LOCK) {
        n = Files[i].ctr;
        if (n == 0x100) n = 0;
        if (n) n--;
        Files[i].ctr = n;
        if (!n) Files[i].fs = 0;
        res = FR_OK;
    } else {
        res = FR_INT_ERR;
    }
    return res;
}

static
void clear_lock ( /* Clear lock entries of the volume */
        FATFS *fs
)
{
    UINT i;

    for (i = 0; i < _FS_LOCK; i++) {
        if (Files[i].fs == fs) Files[i].fs = 0;
    }
}
#endif

/*-----------------------------------------------------------------------*/
/* Move/Flush disk access window                                         */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static FRESULT sync_window(FATFS *fs /* File system object */
) {
    DWORD wsect;
    UINT nf;

    if (fs->wflag) { /* Write back the sector if it is dirty */
        wsect = fs->winsect; /* Current sector number */
        if (disk_write(fs->drv, fs->win, wsect, 1) != RES_OK)
            return FR_DISK_ERR;
        fs->wflag = 0;
        if (wsect >= fs->fatbase && wsect < (fs->fatbase + fs->fsize)) { /* In FAT area? */
            for (nf = fs->n_fats; nf >= 2; nf--) { /* Reflect the change to all FAT copies */
                wsect += fs->fsize;
                disk_write(fs->drv, fs->win, wsect, 1);
            }
        }
    }
    return FR_OK;
}
#endif

static FRESULT move_window(FATFS *fs, /* File system object */
DWORD sector /* Sector number to make appearance in the fs->win[] */
) {
    if (sector != fs->winsect) { /* Changed current window */
#if !_FS_READONLY
        if (sync_window(fs) != FR_OK)
            return FR_DISK_ERR;
#endif
        if (disk_read(fs->drv, fs->win, sector, 1) != RES_OK)
            return FR_DISK_ERR;
        fs->winsect = sector;
    }

    return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Synchronize file system and strage device                             */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static FRESULT sync_fs( /* FR_OK: successful, FR_DISK_ERR: failed */
FATFS *fs /* File system object */
) {
    FRESULT res;

    res = sync_window(fs);
    if (res == FR_OK) {
        /* Update FSInfo sector if needed */
        if (fs->fs_type == FS_FAT32 && fs->fsi_flag) {
            fs->winsect = 0;
            /* Create FSInfo structure */
            mem_set(fs->win, 0, 512);
            ST_WORD(fs->win+BS_55AA, 0xAA55);
            ST_DWORD(fs->win+FSI_LeadSig, 0x41615252);
            ST_DWORD(fs->win+FSI_StrucSig, 0x61417272);
            ST_DWORD(fs->win+FSI_Free_Count, fs->free_clust);
            ST_DWORD(fs->win+FSI_Nxt_Free, fs->last_clust);
            /* Write it into the FSInfo sector */
            disk_write(fs->drv, fs->win, fs->fsi_sector, 1);
            fs->fsi_flag = 0;
        }
        /* Make sure that no pending write process in the physical drive */
        if (disk_ioctl(fs->drv, CTRL_SYNC, 0) != RES_OK)
            res = FR_DISK_ERR;
    }

    return res;
}
#endif

/*-----------------------------------------------------------------------*/
/* Get sector# from cluster#                                             */
/*-----------------------------------------------------------------------*/

DWORD clust2sect( /* !=0: Sector number, 0: Failed - invalid cluster# */
FATFS *fs, /* File system object */
DWORD clst /* Cluster# to be converted */
) {
    clst -= 2;
    if (clst >= (fs->n_fatent - 2))
        return 0; /* Invalid cluster# */
    return clst * fs->csize + fs->database;
}

/*-----------------------------------------------------------------------*/
/* FAT access - Read value of a FAT entry                                */
/*-----------------------------------------------------------------------*/

DWORD get_fat( /* 0xFFFFFFFF:Disk error, 1:Internal error, Else:Cluster status */
FATFS *fs, /* File system object */
DWORD clst /* Cluster# to get the link information */
) {
    UINT wc, bc;
    BYTE *p;

    if (clst < 2 || clst >= fs->n_fatent) /* Check range */
        return 1;

    switch (fs->fs_type) {
    case FS_FAT12:
        bc = (UINT) clst;
        bc += bc / 2;
        if (move_window(fs, fs->fatbase + (bc / SS(fs))))
            break;
        wc = fs->win[bc % SS(fs)];
        bc++;
        if (move_window(fs, fs->fatbase + (bc / SS(fs))))
            break;
        wc |= fs->win[bc % SS(fs)] << 8;
        return (clst & 1) ? (wc >> 4) : (wc & 0xFFF);

    case FS_FAT16:
        if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 2))))
            break;
        p = &fs->win[clst * 2 % SS(fs)];
        return LD_WORD(p) ;

    case FS_FAT32:
        if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 4))))
            break;
        p = &fs->win[clst * 4 % SS(fs)];
        return LD_DWORD(p) & 0x0FFFFFFF;
    }

    return 0xFFFFFFFF; /* An error occurred at the disk I/O layer */
}

/*-----------------------------------------------------------------------*/
/* FAT access - Change value of a FAT entry                              */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY

FRESULT put_fat(FATFS *fs, /* File system object */
DWORD clst, /* Cluster# to be changed in range of 2 to fs->n_fatent - 1 */
DWORD val /* New value to mark the cluster */
) {
    UINT bc;
    BYTE *p;
    FRESULT res;

    if (clst < 2 || clst >= fs->n_fatent) { /* Check range */
        res = FR_INT_ERR;

    } else {
        switch (fs->fs_type) {
        case FS_FAT12:
            bc = (UINT) clst;
            bc += bc / 2;
            res = move_window(fs, fs->fatbase + (bc / SS(fs)));
            if (res != FR_OK)
                break;
            p = &fs->win[bc % SS(fs)];
            *p = (clst & 1) ? ((*p & 0x0F) | ((BYTE) val << 4)) : (BYTE) val;
            bc++;
            fs->wflag = 1;
            res = move_window(fs, fs->fatbase + (bc / SS(fs)));
            if (res != FR_OK)
                break;
            p = &fs->win[bc % SS(fs)];
            *p = (clst & 1) ? (BYTE) (val >> 4) : ((*p & 0xF0) | ((BYTE) (val >> 8) & 0x0F));
            break;

        case FS_FAT16:
            res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 2)));
            if (res != FR_OK)
                break;
            p = &fs->win[clst * 2 % SS(fs)];
            ST_WORD(p, (WORD )val)
            ;
            break;

        case FS_FAT32:
            res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 4)));
            if (res != FR_OK)
                break;
            p = &fs->win[clst * 4 % SS(fs)];
            val |= LD_DWORD(p) & 0xF0000000;
            ST_DWORD(p, val)
            ;
            break;

        default:
            res = FR_INT_ERR;
        }
        fs->wflag = 1;
    }

    return res;
}
#endif /* !_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* FAT handling - Remove a cluster chain                                 */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static FRESULT remove_chain(FATFS *fs, /* File system object */
DWORD clst /* Cluster# to remove a chain from */
) {
    FRESULT res;
    DWORD nxt;
#if _USE_ERASE
    DWORD scl = clst, ecl = clst, rt[2];
#endif

    if (clst < 2 || clst >= fs->n_fatent) { /* Check range */
        res = FR_INT_ERR;

    } else {
        res = FR_OK;
        while (clst < fs->n_fatent) { /* Not a last link? */
            nxt = get_fat(fs, clst); /* Get cluster status */
            if (nxt == 0)
                break; /* Empty cluster? */
            if (nxt == 1) {
                res = FR_INT_ERR;
                break;
            } /* Internal error? */
            if (nxt == 0xFFFFFFFF) {
                res = FR_DISK_ERR;
                break;
            } /* Disk error? */
            res = put_fat(fs, clst, 0); /* Mark the cluster "empty" */
            if (res != FR_OK)
                break;
            if (fs->free_clust != 0xFFFFFFFF) { /* Update FSInfo */
                fs->free_clust++;
                fs->fsi_flag = 1;
            }
#if _USE_ERASE
            if (ecl + 1 == nxt) { /* Is next cluster contiguous? */
                ecl = nxt;
            } else { /* End of contiguous clusters */
                rt[0] = clust2sect(fs, scl); /* Start sector */
                rt[1] = clust2sect(fs, ecl) + fs->csize - 1; /* End sector */
                disk_ioctl(fs->drv, CTRL_ERASE_SECTOR, rt); /* Erase the block */
                scl = ecl = nxt;
            }
#endif
            clst = nxt; /* Next cluster */
        }
    }

    return res;
}
#endif

/*-----------------------------------------------------------------------*/
/* FAT handling - Stretch or Create a cluster chain                      */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static DWORD create_chain( /* 0:No free cluster, 1:Internal error, 0xFFFFFFFF:Disk error, >=2:New cluster# */
FATFS *fs, /* File system object */
DWORD clst /* Cluster# to stretch. 0 means create a new chain. */
) {
    DWORD cs, ncl, scl;
    FRESULT res;

    if (clst == 0) { /* Create a new chain */
        scl = fs->last_clust; /* Get suggested start point */
        if (!scl || scl >= fs->n_fatent)
            scl = 1;
    } else { /* Stretch the current chain */
        cs = get_fat(fs, clst); /* Check the cluster status */
        if (cs < 2)
            return 1; /* It is an invalid cluster */
        if (cs < fs->n_fatent)
            return cs; /* It is already followed by next cluster */
        scl = clst;
    }

    ncl = scl; /* Start cluster */
    for (;;) {
        ncl++; /* Next cluster */
        if (ncl >= fs->n_fatent) { /* Wrap around */
            ncl = 2;
            if (ncl > scl)
                return 0; /* No free cluster */
        }
        cs = get_fat(fs, ncl); /* Get the cluster status */
        if (cs == 0)
            break; /* Found a free cluster */
        if (cs == 0xFFFFFFFF || cs == 1)/* An error occurred */
            return cs;
        if (ncl == scl)
            return 0; /* No free cluster */
    }

    res = put_fat(fs, ncl, 0x0FFFFFFF); /* Mark the new cluster "last link" */
    if (res == FR_OK && clst != 0) {
        res = put_fat(fs, clst, ncl); /* Link it to the previous one if needed */
    }
    if (res == FR_OK) {
        fs->last_clust = ncl; /* Update FSINFO */
        if (fs->free_clust != 0xFFFFFFFF) {
            fs->free_clust--;
            fs->fsi_flag = 1;
        }
    } else {
        ncl = (res == FR_DISK_ERR) ? 0xFFFFFFFF : 1;
    }

    return ncl; /* Return new cluster number or error code */
}
#endif /* !_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* FAT handling - Convert offset into cluster with link map table        */
/*-----------------------------------------------------------------------*/

#if _USE_FASTSEEK
static
DWORD clmt_clust ( /* <2:Error, >=2:Cluster number */
        FIL* fp, /* Pointer to the file object */
        DWORD ofs /* File offset to be converted to cluster# */
)
{
    DWORD cl, ncl, *tbl;

    tbl = fp->cltbl + 1; /* Top of CLMT */
    cl = ofs / SS(fp->fs) / fp->fs->csize; /* Cluster order from top of the file */
    for (;;) {
        ncl = *tbl++; /* Number of cluters in the fragment */
        if (!ncl) return 0; /* End of table? (error) */
        if (cl < ncl) break; /* In this fragment? */
        cl -= ncl; tbl++; /* Next fragment */
    }
    return cl + *tbl; /* Return the cluster number */
}
#endif	/* _USE_FASTSEEK */

/*-----------------------------------------------------------------------*/
/* Directory handling - Set directory index                              */
/*-----------------------------------------------------------------------*/

static FRESULT dir_sdi(DIR *dj, /* Pointer to directory object */
WORD idx /* Index of directory table */
) {
    DWORD clst;
    WORD ic;

    dj->index = idx;
    clst = dj->sclust;
    if (clst == 1 || clst >= dj->fs->n_fatent) /* Check start cluster range */
        return FR_INT_ERR;
    if (!clst && dj->fs->fs_type == FS_FAT32) /* Replace cluster# 0 with root cluster# if in FAT32 */
        clst = dj->fs->dirbase;

    if (clst == 0) { /* Static table (root-dir in FAT12/16) */
        dj->clust = clst;
        if (idx >= dj->fs->n_rootdir) /* Index is out of range */
            return FR_INT_ERR;
        dj->sect = dj->fs->dirbase + idx / (SS(dj->fs) / SZ_DIR); /* Sector# */
    } else { /* Dynamic table (sub-dirs or root-dir in FAT32) */
        ic = SS(dj->fs) / SZ_DIR * dj->fs->csize; /* Entries per cluster */
        while (idx >= ic) { /* Follow cluster chain */
            clst = get_fat(dj->fs, clst); /* Get next cluster */
            if (clst == 0xFFFFFFFF)
                return FR_DISK_ERR; /* Disk error */
            if (clst < 2 || clst >= dj->fs->n_fatent) /* Reached to end of table or int error */
                return FR_INT_ERR;
            idx -= ic;
        }
        dj->clust = clst;
        dj->sect = clust2sect(dj->fs, clst) + idx / (SS(dj->fs) / SZ_DIR); /* Sector# */
    }

    dj->dir = dj->fs->win + (idx % (SS(dj->fs) / SZ_DIR)) * SZ_DIR; /* Ptr to the entry in the sector */

    return FR_OK; /* Seek succeeded */
}

/*-----------------------------------------------------------------------*/
/* Directory handling - Move directory table index next                  */
/*-----------------------------------------------------------------------*/

static FRESULT dir_next( /* FR_OK:Succeeded, FR_NO_FILE:End of table, FR_DENIED:Could not stretch */
DIR *dj, /* Pointer to the directory object */
int stretch /* 0: Do not stretch table, 1: Stretch table if needed */
) {
    DWORD clst;
    WORD i;

//	stretch = stretch;		/* To suppress warning on read-only cfg. */
    i = dj->index + 1;
    if (!i || !dj->sect) /* Report EOT when index has reached 65535 */
        return FR_NO_FILE;

    if (!(i % (SS(dj->fs) / SZ_DIR))) { /* Sector changed? */
        dj->sect++; /* Next sector */

        if (dj->clust == 0) { /* Static table */
            if (i >= dj->fs->n_rootdir) /* Report EOT when end of table */
                return FR_NO_FILE;
        } else { /* Dynamic table */
            if (((i / (SS(dj->fs) / SZ_DIR)) & (dj->fs->csize - 1)) == 0) { /* Cluster changed? */
                clst = get_fat(dj->fs, dj->clust); /* Get next cluster */
                if (clst <= 1)
                    return FR_INT_ERR;
                if (clst == 0xFFFFFFFF)
                    return FR_DISK_ERR;
                if (clst >= dj->fs->n_fatent) { /* When it reached end of dynamic table */
#if !_FS_READONLY
                    BYTE c;
                    if (!stretch)
                        return FR_NO_FILE; /* When do not stretch, report EOT */
                    clst = create_chain(dj->fs, dj->clust); /* Stretch cluster chain */
                    if (clst == 0)
                        return FR_DENIED; /* No free cluster */
                    if (clst == 1)
                        return FR_INT_ERR;
                    if (clst == 0xFFFFFFFF)
                        return FR_DISK_ERR;
                    /* Clean-up stretched table */
                    if (sync_window(dj->fs))
                        return FR_DISK_ERR; /* Flush active window */
                    mem_set(dj->fs->win, 0, SS(dj->fs)); /* Clear window buffer */
                    dj->fs->winsect = clust2sect(dj->fs, clst); /* Cluster start sector */
                    for (c = 0; c < dj->fs->csize; c++) { /* Fill the new cluster with 0 */
                        dj->fs->wflag = 1;
                        if (sync_window(dj->fs))
                            return FR_DISK_ERR;
                        dj->fs->winsect++;
                    }
                    dj->fs->winsect -= c; /* Rewind window address */
#else
                    return FR_NO_FILE; /* Report EOT */
#endif
                }
                dj->clust = clst; /* Initialize data for new cluster */
                dj->sect = clust2sect(dj->fs, clst);
            }
        }
    }

    dj->index = i;
    dj->dir = dj->fs->win + (i % (SS(dj->fs) / SZ_DIR)) * SZ_DIR;

    return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Directory handling - Reserve directory entry                          */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static FRESULT dir_alloc(DIR* dj, /* Pointer to the directory object */
UINT nent /* Number of contiguous entries to allocate (1-21) */
) {
    FRESULT res;
    UINT n;

    res = dir_sdi(dj, 0);
    if (res == FR_OK) {
        n = 0;
        do {
            res = move_window(dj->fs, dj->sect);
            if (res != FR_OK)
                break;
            if (dj->dir[0] == DDE || dj->dir[0] == 0) { /* Is it a blank entry? */
                if (++n == nent)
                    break; /* A block of contiguous entry is found */
            } else {
                n = 0; /* Not a blank entry. Restart to search */
            }
            res = dir_next(dj, 1); /* Next entry with table stretch enabled */
        } while (res == FR_OK);
    }
    return res;
}
#endif

/*-----------------------------------------------------------------------*/
/* Directory handling - Load/Store start cluster number                  */
/*-----------------------------------------------------------------------*/

static DWORD ld_clust(FATFS *fs, /* Pointer to the fs object */
BYTE *dir /* Pointer to the directory entry */
) {
    DWORD cl;

    cl = LD_WORD(dir+DIR_FstClusLO);
    if (fs->fs_type == FS_FAT32)
        cl |= (DWORD) LD_WORD(dir+DIR_FstClusHI) << 16;

    return cl;
}

#if !_FS_READONLY
static
void st_clust(BYTE *dir, /* Pointer to the directory entry */
DWORD cl /* Value to be set */
) {
    ST_WORD(dir+DIR_FstClusLO, cl);
    ST_WORD(dir+DIR_FstClusHI, cl >> 16);
}
#endif

/*-----------------------------------------------------------------------*/
/* LFN handling - Test/Pick/Fit an LFN segment from/to directory entry   */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static const BYTE LfnOfs[] = { 1, 3, 5, 7, 9, 14, 16, 18, 20, 22, 24, 28, 30 }; /* Offset of LFN chars in the directory entry */

static
int cmp_lfn( /* 1:Matched, 0:Not matched */
WCHAR *lfnbuf, /* Pointer to the LFN to be compared */
BYTE *dir /* Pointer to the directory entry containing a part of LFN */
) {
    UINT i, s;
    WCHAR wc, uc;

    i = ((dir[LDIR_Ord] & ~LLE) - 1) * 13; /* Get offset in the LFN buffer */
    s = 0;
    wc = 1;
    do {
        uc = LD_WORD(dir+LfnOfs[s]); /* Pick an LFN character from the entry */
        if (wc) { /* Last char has not been processed */
            wc = ff_wtoupper(uc); /* Convert it to upper case */
            if (i >= _MAX_LFN || wc != ff_wtoupper(lfnbuf[i++])) /* Compare it */
                return 0; /* Not matched */
        } else {
            if (uc != 0xFFFF)
                return 0; /* Check filler */
        }
    } while (++s < 13); /* Repeat until all chars in the entry are checked */

    if ((dir[LDIR_Ord] & LLE) && wc && lfnbuf[i]) /* Last segment matched but different length */
        return 0;

    return 1; /* The part of LFN matched */
}

static
int pick_lfn( /* 1:Succeeded, 0:Buffer overflow */
WCHAR *lfnbuf, /* Pointer to the Unicode-LFN buffer */
BYTE *dir /* Pointer to the directory entry */
) {
    UINT i, s;
    WCHAR wc, uc;

    i = ((dir[LDIR_Ord] & 0x3F) - 1) * 13; /* Offset in the LFN buffer */

    s = 0;
    wc = 1;
    do {
        uc = LD_WORD(dir+LfnOfs[s]); /* Pick an LFN character from the entry */
        if (wc) { /* Last char has not been processed */
            if (i >= _MAX_LFN)
                return 0; /* Buffer overflow? */
            lfnbuf[i++] = wc = uc; /* Store it */
        } else {
            if (uc != 0xFFFF)
                return 0; /* Check filler */
        }
    } while (++s < 13); /* Read all character in the entry */

    if (dir[LDIR_Ord] & LLE) { /* Put terminator if it is the last LFN part */
        if (i >= _MAX_LFN)
            return 0; /* Buffer overflow? */
        lfnbuf[i] = 0;
    }

    return 1;
}

#if !_FS_READONLY
static
void fit_lfn(const WCHAR *lfnbuf, /* Pointer to the LFN buffer */
BYTE *dir, /* Pointer to the directory entry */
BYTE ord, /* LFN order (1-20) */
BYTE sum /* SFN sum */
) {
    UINT i, s;
    WCHAR wc;

    dir[LDIR_Chksum] = sum; /* Set check sum */
    dir[LDIR_Attr] = AM_LFN; /* Set attribute. LFN entry */
    dir[LDIR_Type] = 0;
    ST_WORD(dir+LDIR_FstClusLO, 0);

    i = (ord - 1) * 13; /* Get offset in the LFN buffer */
    s = wc = 0;
    do {
        if (wc != 0xFFFF)
            wc = lfnbuf[i++]; /* Get an effective char */
        ST_WORD(dir + LfnOfs[s], wc); /* Put it */
        if (!wc)
            wc = 0xFFFF; /* Padding chars following last char */
    } while (++s < 13);
    if (wc == 0xFFFF || !lfnbuf[i])
        ord |= LLE; /* Bottom LFN part is the start of LFN sequence */
    dir[LDIR_Ord] = ord; /* Set the LFN order */
}

#endif
#endif

/*-----------------------------------------------------------------------*/
/* Create numbered name                                                  */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
void gen_numname(BYTE *dst, /* Pointer to generated SFN */
const BYTE *src, /* Pointer to source SFN to be modified */
const WCHAR *lfn, /* Pointer to LFN */
WORD seq /* Sequence number */
) {
    BYTE ns[8], c;
    UINT i, j;

    mem_cpy(dst, src, 11);

    if (seq > 5) { /* On many collisions, generate a hash number instead of sequential number */
        do
            seq = (seq >> 1) + (seq << 15) + (WORD) *lfn++;
        while (*lfn);
    }

    /* itoa (hexdecimal) */
    i = 7;
    do {
        c = (seq % 16) + '0';
        if (c > '9')
            c += 7;
        ns[i--] = c;
        seq /= 16;
    } while (seq);
    ns[i] = '~';

    /* Append the number */
    for (j = 0; j < i && dst[j] != ' '; j++) {
        if (IsDBCS1(dst[j])) {
            if (j == i - 1)
                break;
            j++;
        }
    }
    do {
        dst[j++] = (i < 8) ? ns[i++] : ' ';
    } while (j < 8);
}
#endif

/*-----------------------------------------------------------------------*/
/* Calculate sum of an SFN                                               */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static BYTE sum_sfn(const BYTE *dir /* Ptr to directory entry */
) {
    BYTE sum = 0;
    UINT n = 11;

    do
        sum = (sum >> 1) + (sum << 7) + *dir++;
    while (--n);
    return sum;
}
#endif

/*-----------------------------------------------------------------------*/
/* Directory handling - Find an object in the directory                  */
/*-----------------------------------------------------------------------*/

static FRESULT dir_find(DIR *dj /* Pointer to the directory object linked to the file name */
) {
    FRESULT res;
    BYTE c, *dir;
#if _USE_LFN
    BYTE a, ord, sum;
#endif

    res = dir_sdi(dj, 0); /* Rewind directory object */
    if (res != FR_OK)
        return res;

#if _USE_LFN
    ord = sum = 0xFF;
#endif
    do {
        res = move_window(dj->fs, dj->sect);
        if (res != FR_OK)
            break;
        dir = dj->dir; /* Ptr to the directory entry of current index */
        c = dir[DIR_Name];
        if (c == 0) {
            res = FR_NO_FILE;
            break;
        } /* Reached to end of table */
#if _USE_LFN	/* LFN configuration */
        a = dir[DIR_Attr] & AM_MASK;
        if (c == DDE || ((a & AM_VOL) && a != AM_LFN)) { /* An entry without valid data */
            ord = 0xFF;
        } else {
            if (a == AM_LFN) { /* An LFN entry is found */
                if (dj->lfn) {
                    if (c & LLE) { /* Is it start of LFN sequence? */
                        sum = dir[LDIR_Chksum];
                        c &= ~LLE;
                        ord = c; /* LFN start order */
                        dj->lfn_idx = dj->index;
                    }
                    /* Check validity of the LFN entry and compare it with given name */
                    ord = (c == ord && sum == dir[LDIR_Chksum] && cmp_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
                }
            } else { /* An SFN entry is found */
                if (!ord && sum == sum_sfn(dir))
                    break; /* LFN matched? */
                ord = 0xFF;
                dj->lfn_idx = 0xFFFF; /* Reset LFN sequence */
                if (!(dj->fn[NS] & NS_LOSS) && !mem_cmp(dir, dj->fn, 11))
                    break; /* SFN matched? */
            }
        }
#else		/* Non LFN configuration */
        if (!(dir[DIR_Attr] & AM_VOL) && !mem_cmp(dir, dj->fn, 11)) /* Is it a valid entry? */
        break;
#endif
        res = dir_next(dj, 0); /* Next entry */
    } while (res == FR_OK);

    return res;
}

/*-----------------------------------------------------------------------*/
/* Read an object from the directory                                     */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1 || _USE_LABEL || _FS_RPATH >= 2
static FRESULT dir_read(DIR *dj, /* Pointer to the directory object */
int vol /* Filtered by 0:file/dir or 1:volume label */
) {
    FRESULT res;
    BYTE a, c, *dir;
#if _USE_LFN
    BYTE ord = 0xFF, sum = 0xFF;
#endif

    res = FR_NO_FILE;
    while (dj->sect) {
        res = move_window(dj->fs, dj->sect);
        if (res != FR_OK)
            break;
        dir = dj->dir; /* Ptr to the directory entry of current index */
        c = dir[DIR_Name];
        if (c == 0) {
            res = FR_NO_FILE;
            break;
        } /* Reached to end of table */
        a = dir[DIR_Attr] & AM_MASK;
#if _USE_LFN	/* LFN configuration */
        if (c == DDE || (!_FS_RPATH && c == '.') || (a == AM_VOL) != vol) { /* An entry without valid data */
            ord = 0xFF;
        } else {
            if (a == AM_LFN) { /* An LFN entry is found */
                if (c & LLE) { /* Is it start of LFN sequence? */
                    sum = dir[LDIR_Chksum];
                    c &= ~LLE;
                    ord = c;
                    dj->lfn_idx = dj->index;
                }
                /* Check LFN validity and capture it */
                ord = (c == ord && sum == dir[LDIR_Chksum] && pick_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
            } else { /* An SFN entry is found */
                if (ord || sum != sum_sfn(dir)) /* Is there a valid LFN? */
                    dj->lfn_idx = 0xFFFF; /* It has no LFN. */
                break;
            }
        }
#else		/* Non LFN configuration */
        if (c != DDE && (_FS_RPATH || c != '.') && a != AM_LFN && (a == AM_VOL) == vol) /* Is it a valid entry? */
        break;
#endif
        res = dir_next(dj, 0); /* Next entry */
        if (res != FR_OK)
            break;
    }

    if (res != FR_OK)
        dj->sect = 0;

    return res;
}
#endif	/* _FS_MINIMIZE <= 1 || _USE_LABEL || _FS_RPATH >= 2 */

/*-----------------------------------------------------------------------*/
/* Register an object to the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static FRESULT dir_register( /* FR_OK:Successful, FR_DENIED:No free entry or too many SFN collision, FR_DISK_ERR:Disk error */
DIR *dj /* Target directory with object name to be created */
) {
    FRESULT res;
#if _USE_LFN	/* LFN configuration */
    WORD n, ne;
    BYTE sn[12], *fn, sum;
    WCHAR *lfn;

    fn = dj->fn;
    lfn = dj->lfn;
    mem_cpy(sn, fn, 12);

    if (_FS_RPATH && (sn[NS] & NS_DOT)) /* Cannot create dot entry */
        return FR_INVALID_NAME;

    if (sn[NS] & NS_LOSS) { /* When LFN is out of 8.3 format, generate a numbered name */
        fn[NS] = 0;
        dj->lfn = 0; /* Find only SFN */
        for (n = 1; n < 100; n++) {
            gen_numname(fn, sn, lfn, n); /* Generate a numbered name */
            res = dir_find(dj); /* Check if the name collides with existing SFN */
            if (res != FR_OK)
                break;
        }
        if (n == 100)
            return FR_DENIED; /* Abort if too many collisions */
        if (res != FR_NO_FILE)
            return res; /* Abort if the result is other than 'not collided' */
        fn[NS] = sn[NS];
        dj->lfn = lfn;
    }

    if (sn[NS] & NS_LFN) { /* When LFN is to be created, allocate entries for an SFN + LFNs. */
        for (n = 0; lfn[n]; n++)
            ;
        ne = (n + 25) / 13;
    } else { /* Otherwise allocate an entry for an SFN  */
        ne = 1;
    }
    res = dir_alloc(dj, ne); /* Allocate entries */

    if (res == FR_OK && --ne) { /* Set LFN entry if needed */
        res = dir_sdi(dj, (WORD) (dj->index - ne));
        if (res == FR_OK) {
            sum = sum_sfn(dj->fn); /* Sum value of the SFN tied to the LFN */
            do { /* Store LFN entries in bottom first */
                res = move_window(dj->fs, dj->sect);
                if (res != FR_OK)
                    break;
                fit_lfn(dj->lfn, dj->dir, (BYTE) ne, sum);
                dj->fs->wflag = 1;
                res = dir_next(dj, 0); /* Next entry */
            } while (res == FR_OK && --ne);
        }
    }
#else	/* Non LFN configuration */
    res = dir_alloc(dj, 1); /* Allocate an entry for SFN */
#endif

    if (res == FR_OK) { /* Set SFN entry */
        res = move_window(dj->fs, dj->sect);
        if (res == FR_OK) {
            mem_set(dj->dir, 0, SZ_DIR); /* Clean the entry */
            mem_cpy(dj->dir, dj->fn, 11); /* Put SFN */
#if _USE_LFN
            dj->dir[DIR_NTres] = *(dj->fn + NS) & (NS_BODY | NS_EXT); /* Put NT flag */
#endif
            dj->fs->wflag = 1;
        }
    }

    return res;
}
#endif /* !_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* Remove an object from the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY && !_FS_MINIMIZE
static FRESULT dir_remove( /* FR_OK: Successful, FR_DISK_ERR: A disk error */
DIR *dj /* Directory object pointing the entry to be removed */
) {
    FRESULT res;
#if _USE_LFN	/* LFN configuration */
    WORD i;

    i = dj->index; /* SFN index */
    res = dir_sdi(dj, (WORD) ((dj->lfn_idx == 0xFFFF) ? i : dj->lfn_idx)); /* Goto the SFN or top of the LFN entries */
    if (res == FR_OK) {
        do {
            res = move_window(dj->fs, dj->sect);
            if (res != FR_OK)
                break;
            *dj->dir = DDE; /* Mark the entry "deleted" */
            dj->fs->wflag = 1;
            if (dj->index >= i)
                break; /* When reached SFN, all entries of the object has been deleted. */
            res = dir_next(dj, 0); /* Next entry */
        } while (res == FR_OK);
        if (res == FR_NO_FILE)
            res = FR_INT_ERR;
    }

#else			/* Non LFN configuration */
    res = dir_sdi(dj, dj->index);
    if (res == FR_OK) {
        res = move_window(dj->fs, dj->sect);
        if (res == FR_OK) {
            *dj->dir = DDE; /* Mark the entry "deleted" */
            dj->fs->wflag = 1;
        }
    }
#endif

    return res;
}
#endif /* !_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* Pick a segment and create the object name in directory form           */
/*-----------------------------------------------------------------------*/

static FRESULT create_name(DIR *dj, /* Pointer to the directory object */
const TCHAR **path /* Pointer to pointer to the segment in the path string */
) {
#if _USE_LFN	/* LFN configuration */
    BYTE b, cf;
    WCHAR w, *lfn;
    UINT i, ni, si, di;
    const TCHAR *p;

    /* Create LFN in Unicode */
    for (p = *path; *p == '/' || *p == '\\'; p++)
        ; /* Strip duplicated separator */
    lfn = dj->lfn;
    si = di = 0;
    for (;;) {
        w = p[si++]; /* Get a character */
        if (w < ' ' || w == '/' || w == '\\')
            break; /* Break on end of segment */
        if (di >= _MAX_LFN) /* Reject too long name */
            return FR_INVALID_NAME;
#if !_LFN_UNICODE
        w &= 0xFF;
        if (IsDBCS1(w)) { /* Check if it is a DBC 1st byte (always false on SBCS cfg) */
            b = (BYTE) p[si++]; /* Get 2nd byte */
            if (!IsDBCS2(b))
                return FR_INVALID_NAME; /* Reject invalid sequence */
            w = (w << 8) + b; /* Create a DBC */
        }
        w = ff_convert(w, 1); /* Convert ANSI/OEM to Unicode */
        if (!w)
            return FR_INVALID_NAME; /* Reject invalid code */
#endif
        if (w < 0x80 && chk_chr("\"*:<>\?|\x7F", w)) /* Reject illegal chars for LFN */
            return FR_INVALID_NAME;
        lfn[di++] = w; /* Store the Unicode char */
    }
    *path = &p[si]; /* Return pointer to the next segment */
    cf = (w < ' ') ? NS_LAST : 0; /* Set last segment flag if end of path */
#if _FS_RPATH
    if ((di == 1 && lfn[di-1] == '.') || /* Is this a dot entry? */
            (di == 2 && lfn[di-1] == '.' && lfn[di-2] == '.')) {
        lfn[di] = 0;
        for (i = 0; i < 11; i++)
        dj->fn[i] = (i < di) ? '.' : ' ';
        dj->fn[i] = cf | NS_DOT; /* This is a dot entry */
        return FR_OK;
    }
#endif
    while (di) { /* Strip trailing spaces and dots */
        w = lfn[di - 1];
        if (w != ' ' && w != '.')
            break;
        di--;
    }
    if (!di)
        return FR_INVALID_NAME; /* Reject nul string */

    lfn[di] = 0; /* LFN is created */

    /* Create SFN in directory form */
    mem_set(dj->fn, ' ', 11);
    for (si = 0; lfn[si] == ' ' || lfn[si] == '.'; si++)
        ; /* Strip leading spaces and dots */
    if (si)
        cf |= NS_LOSS | NS_LFN;
    while (di && lfn[di - 1] != '.')
        di--; /* Find extension (di<=si: no extension) */

    b = i = 0;
    ni = 8;
    for (;;) {
        w = lfn[si++]; /* Get an LFN char */
        if (!w)
            break; /* Break on end of the LFN */
        if (w == ' ' || (w == '.' && si != di)) { /* Remove spaces and dots */
            cf |= NS_LOSS | NS_LFN;
            continue;
        }

        if (i >= ni || si == di) { /* Extension or end of SFN */
            if (ni == 11) { /* Long extension */
                cf |= NS_LOSS | NS_LFN;
                break;
            }
            if (si != di)
                cf |= NS_LOSS | NS_LFN; /* Out of 8.3 format */
            if (si > di)
                break; /* No extension */
            si = di;
            i = 8;
            ni = 11; /* Enter extension section */
            b <<= 2;
            continue;
        }

        if (w >= 0x80) { /* Non ASCII char */
#ifdef _EXCVT
            w = ff_convert(w, 0); /* Unicode -> OEM code */
            if (w)
                w = ExCvt[w - 0x80]; /* Convert extended char to upper (SBCS) */
#else
            w = ff_convert(ff_wtoupper(w), 0); /* Upper converted Unicode -> OEM code */
#endif
            cf |= NS_LFN; /* Force create LFN entry */
        }

        if (_DF1S && w >= 0x100) { /* Double byte char (always false on SBCS cfg) */
            if (i >= ni - 1) {
                cf |= NS_LOSS | NS_LFN;
                i = ni;
                continue;
            }
            dj->fn[i++] = (BYTE) (w >> 8);
        } else { /* Single byte char */
            if (!w || chk_chr("+,;=[]", w)) { /* Replace illegal chars for SFN */
                w = '_';
                cf |= NS_LOSS | NS_LFN;/* Lossy conversion */
            } else {
                if (IsUpper(w)) { /* ASCII large capital */
                    b |= 2;
                } else {
                    if (IsLower(w)) { /* ASCII small capital */
                        b |= 1;
                        w -= 0x20;
                    }
                }
            }
        }
        dj->fn[i++] = (BYTE) w;
    }

    if (dj->fn[0] == DDE)
        dj->fn[0] = NDDE; /* If the first char collides with deleted mark, replace it with 0x05 */

    if (ni == 8)
        b <<= 2;
    if ((b & 0x0C) == 0x0C || (b & 0x03) == 0x03) /* Create LFN entry when there are composite capitals */
        cf |= NS_LFN;
    if (!(cf & NS_LFN)) { /* When LFN is in 8.3 format without extended char, NT flags are created */
        if ((b & 0x03) == 0x01)
            cf |= NS_EXT; /* NT flag (Extension has only small capital) */
        if ((b & 0x0C) == 0x04)
            cf |= NS_BODY; /* NT flag (Filename has only small capital) */
    }

    dj->fn[NS] = cf; /* SFN is created */

    return FR_OK;

#else	/* Non-LFN configuration */
    BYTE b, c, d, *sfn;
    UINT ni, si, i;
    const char *p;

    /* Create file name in directory form */
    for (p = *path; *p == '/' || *p == '\\'; p++); /* Strip duplicated separator */
    sfn = dj->fn;
    mem_set(sfn, ' ', 11);
    si = i = b = 0; ni = 8;
#if _FS_RPATH
    if (p[si] == '.') { /* Is this a dot entry? */
        for (;;) {
            c = (BYTE)p[si++];
            if (c != '.' || si >= 3) break;
            sfn[i++] = c;
        }
        if (c != '/' && c != '\\' && c > ' ') return FR_INVALID_NAME;
        *path = &p[si]; /* Return pointer to the next segment */
        sfn[NS] = (c <= ' ') ? NS_LAST | NS_DOT : NS_DOT; /* Set last segment flag if end of path */
        return FR_OK;
    }
#endif
    for (;;) {
        c = (BYTE)p[si++];
        if (c <= ' ' || c == '/' || c == '\\') break; /* Break on end of segment */
        if (c == '.' || i >= ni) {
            if (ni != 8 || c != '.') return FR_INVALID_NAME;
            i = 8; ni = 11;
            b <<= 2; continue;
        }
        if (c >= 0x80) { /* Extended char? */
            b |= 3; /* Eliminate NT flag */
#ifdef _EXCVT
            c = ExCvt[c - 0x80]; /* To upper extended chars (SBCS cfg) */
#else
#if !_DF1S
            return FR_INVALID_NAME; /* Reject extended chars (ASCII cfg) */
#endif
#endif
        }
        if (IsDBCS1(c)) { /* Check if it is a DBC 1st byte (always false on SBCS cfg) */
            d = (BYTE)p[si++]; /* Get 2nd byte */
            if (!IsDBCS2(d) || i >= ni - 1) /* Reject invalid DBC */
            return FR_INVALID_NAME;
            sfn[i++] = c;
            sfn[i++] = d;
        } else { /* Single byte code */
            if (chk_chr("\"*+,:;<=>\?[]|\x7F", c)) /* Reject illegal chrs for SFN */
            return FR_INVALID_NAME;
            if (IsUpper(c)) { /* ASCII large capital? */
                b |= 2;
            } else {
                if (IsLower(c)) { /* ASCII small capital? */
                    b |= 1; c -= 0x20;
                }
            }
            sfn[i++] = c;
        }
    }
    *path = &p[si]; /* Return pointer to the next segment */
    c = (c <= ' ') ? NS_LAST : 0; /* Set last segment flag if end of path */

    if (!i) return FR_INVALID_NAME; /* Reject nul string */
    if (sfn[0] == DDE) sfn[0] = NDDE; /* When first char collides with DDE, replace it with 0x05 */

    if (ni == 8) b <<= 2;
    if ((b & 0x03) == 0x01) c |= NS_EXT; /* NT flag (Name extension has only small capital) */
    if ((b & 0x0C) == 0x04) c |= NS_BODY; /* NT flag (Name body has only small capital) */

    sfn[NS] = c; /* Store NT flag, File name is created */

    return FR_OK;
#endif
}

/*-----------------------------------------------------------------------*/
/* Get file information from directory entry                             */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1 || _FS_RPATH >= 2
static
void get_fileinfo( /* No return code */
DIR *dj, /* Pointer to the directory object */
FILINFO *fno /* Pointer to the file information to be filled */
) {
    UINT i;
    BYTE nt, *dir;
    TCHAR *p, c;

    p = fno->fname;
    if (dj->sect) {
        dir = dj->dir;
        nt = dir[DIR_NTres]; /* NT flag */
        for (i = 0; i < 8; i++) { /* Copy name body */
            c = dir[i];
            if (c == ' ')
                break;
            if (c == NDDE)
                c = (TCHAR) DDE;
            if (_USE_LFN && (nt & NS_BODY) && IsUpper(c))
                c += 0x20;
#if _LFN_UNICODE
            if (IsDBCS1(c) && i < 7 && IsDBCS2(dir[i+1]))
            c = (c << 8) | dir[++i];
            c = ff_convert(c, 1);
            if (!c) c = '?';
#endif
            *p++ = c;
        }
        if (dir[8] != ' ') { /* Copy name extension */
            *p++ = '.';
            for (i = 8; i < 11; i++) {
                c = dir[i];
                if (c == ' ')
                    break;
                if (_USE_LFN && (nt & NS_EXT) && IsUpper(c))
                    c += 0x20;
#if _LFN_UNICODE
                if (IsDBCS1(c) && i < 10 && IsDBCS2(dir[i+1]))
                c = (c << 8) | dir[++i];
                c = ff_convert(c, 1);
                if (!c) c = '?';
#endif
                *p++ = c;
            }
        }
        fno->fattrib = dir[DIR_Attr]; /* Attribute */
        fno->fsize = LD_DWORD(dir+DIR_FileSize); /* Size */
        fno->fdate = LD_WORD(dir+DIR_WrtDate); /* Date */
        fno->ftime = LD_WORD(dir+DIR_WrtTime); /* Time */
    }
    *p = 0; /* Terminate SFN str by a \0 */

#if _USE_LFN
    if (fno->lfname && fno->lfsize) {
        TCHAR *tp = fno->lfname;
        WCHAR w, *lfn;

        i = 0;
        if (dj->sect && dj->lfn_idx != 0xFFFF) {/* Get LFN if available */
            lfn = dj->lfn;
            while ((w = *lfn++) != 0) { /* Get an LFN char */
#if !_LFN_UNICODE
                w = ff_convert(w, 0); /* Unicode -> OEM conversion */
                if (!w) {
                    i = 0;
                    break;
                } /* Could not convert, no LFN */
                if (_DF1S && w >= 0x100) /* Put 1st byte if it is a DBC (always false on SBCS cfg) */
                    tp[i++] = (TCHAR) (w >> 8);
#endif
                if (i >= fno->lfsize - 1) {
                    i = 0;
                    break;
                } /* Buffer overflow, no LFN */
                tp[i++] = (TCHAR) w;
            }
        }
        tp[i] = 0; /* Terminate the LFN str by a \0 */
    }
#endif
}
#endif /* _FS_MINIMIZE <= 1 || _FS_RPATH >= 2*/

/*-----------------------------------------------------------------------*/
/* Follow a file path                                                    */
/*-----------------------------------------------------------------------*/

static FRESULT follow_path( /* FR_OK(0): successful, !=0: error code */
DIR *dj, /* Directory object to return last directory and found object */
const TCHAR *path /* Full-path string to find a file or directory */
) {
    FRESULT res;
    BYTE *dir, ns;

#if _FS_RPATH
    if (*path == '/' || *path == '\\') { /* There is a heading separator */
        path++; dj->sclust = 0; /* Strip it and start from the root dir */
    } else { /* No heading separator */
        dj->sclust = dj->fs->cdir; /* Start from the current dir */
    }
#else
    if (*path == '/' || *path == '\\') /* Strip heading separator if exist */
        path++;
    dj->sclust = 0; /* Start from the root dir */
#endif

    if ((UINT) *path < ' ') { /* Nul path means the start directory itself */
        res = dir_sdi(dj, 0);
        dj->dir = 0;
    } else { /* Follow path */
        for (;;) {
            res = create_name(dj, &path); /* Get a segment */
            if (res != FR_OK)
                break;
            res = dir_find(dj); /* Find it */
            ns = *(dj->fn + NS);
            if (res != FR_OK) { /* Failed to find the object */
                if (res != FR_NO_FILE)
                    break; /* Abort if any hard error occurred */
                /* Object not found */
                if (_FS_RPATH && (ns & NS_DOT)) { /* If dot entry is not exit */
                    dj->sclust = 0;
                    dj->dir = 0; /* It is the root dir */
                    res = FR_OK;
                    if (!(ns & NS_LAST))
                        continue;
                } else { /* Could not find the object */
                    if (!(ns & NS_LAST))
                        res = FR_NO_PATH;
                }
                break;
            }
            if (ns & NS_LAST)
                break; /* Last segment match. Function completed. */
            dir = dj->dir; /* There is next segment. Follow the sub directory */
            if (!(dir[DIR_Attr] & AM_DIR)) { /* Cannot follow because it is a file */
                res = FR_NO_PATH;
                break;
            }
            dj->sclust = ld_clust(dj->fs, dir);
        }
    }

    return res;
}

/*-----------------------------------------------------------------------*/
/* Load a sector and check if it is an FAT Volume Boot Record            */
/*-----------------------------------------------------------------------*/

static BYTE check_fs( /* 0:FAT-VBR, 1:Any BR but not FAT, 2:Not a BR, 3:Disk error */
FATFS *fs, /* File system object */
DWORD sect /* Sector# (lba) to check if it is an FAT boot record or not */
) {
    if (disk_read(fs->drv, fs->win, sect, 1) != RES_OK) /* Load boot record */
        return 3;
    if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55) /* Check record signature (always placed at offset 510 even if the sector size is >512) */
        return 2;

    if ((LD_DWORD(&fs->win[BS_FilSysType]) & 0xFFFFFF) == 0x544146) /* Check "FAT" string */
        return 0;
    if ((LD_DWORD(&fs->win[BS_FilSysType32]) & 0xFFFFFF) == 0x544146)
        return 0;

    return 1;
}

/*-----------------------------------------------------------------------*/
/* Check if the file system object is valid or not                       */
/*-----------------------------------------------------------------------*/

static FRESULT chk_mounted( /* FR_OK(0): successful, !=0: any error occurred */
const TCHAR **path, /* Pointer to pointer to the path name (drive number) */
FATFS **rfs, /* Pointer to pointer to the found file system object */
BYTE wmode /* !=0: Check write protection for write access */
) {
    BYTE fmt, b, pi, *tbl;
    UINT vol;
    DSTATUS stat;
    DWORD bsect, fasize, tsect, sysect, nclst, szbfat;
    WORD nrsv;
    const TCHAR *p = *path;
    FATFS *fs;

    /* Get logical drive number from the path name */
    vol = p[0] - '0'; /* Is there a drive number? */
    if (vol <= 9 && p[1] == ':') { /* Found a drive number, get and strip it */
        p += 2;
        *path = p; /* Return pointer to the path name */
    } else { /* No drive number, use default drive */
#if _FS_RPATH
        vol = CurrVol; /* Use current drive */
#else
        vol = 0; /* Use drive 0 */
#endif
    }

    /* Check if the file system object is valid or not */
    *rfs = 0;
    if (vol >= _VOLUMES) /* Is the drive number valid? */
        return FR_INVALID_DRIVE;
    fs = FatFs[vol]; /* Get corresponding file system object */
    if (!fs)
        return FR_NOT_ENABLED; /* Is the file system object available? */

    ENTER_FF(fs); /* Lock volume */

    *rfs = fs; /* Return pointer to the corresponding file system object */
    if (fs->fs_type) { /* If the volume has been mounted */
        stat = disk_status(fs->drv);
        if (!(stat & STA_NOINIT)) { /* and the physical drive is kept initialized (has not been changed), */
            if (!_FS_READONLY && wmode && (stat & STA_PROTECT)) /* Check write protection if needed */
                return FR_WRITE_PROTECTED;
            return FR_OK; /* The file system object is valid */
        }
    }

    /* The file system object is not valid. */
    /* Following code attempts to mount the volume. (analyze BPB and initialize the fs object) */

    fs->fs_type = 0; /* Clear the file system object */
    fs->drv = LD2PD(vol); /* Bind the logical drive and a physical drive */
    stat = disk_initialize(fs->drv); /* Initialize the physical drive */
    if (stat & STA_NOINIT) /* Check if the initialization succeeded */
        return FR_NOT_READY; /* Failed to initialize due to no medium or hard error */
    if (!_FS_READONLY && wmode && (stat & STA_PROTECT)) /* Check disk write protection if needed */
        return FR_WRITE_PROTECTED;
#if _MAX_SS != 512						/* Get disk sector size (variable sector size cfg only) */
    if (disk_ioctl(fs->drv, GET_SECTOR_SIZE, &fs->ssize) != RES_OK)
    return FR_DISK_ERR;
#endif
    /* Search FAT partition on the drive. Supports only generic partitions, FDISK and SFD. */
    fmt = check_fs(fs, bsect = 0); /* Load sector 0 and check if it is an FAT-VBR (in SFD) */
    if (LD2PT(vol) && !fmt)
        fmt = 1; /* Force non-SFD if the volume is forced partition */
    if (fmt == 1) { /* Not an FAT-VBR, the physical drive can be partitioned */
        /* Check the partition listed in the partition table */
        pi = LD2PT(vol);
        if (pi)
            pi--;
        tbl = &fs->win[MBR_Table + pi * SZ_PTE];/* Partition table */
        if (tbl[4]) { /* Is the partition existing? */
            bsect = LD_DWORD(&tbl[8]); /* Partition offset in LBA */
            fmt = check_fs(fs, bsect); /* Check the partition */
        }
    }
    if (fmt == 3)
        return FR_DISK_ERR;
    if (fmt)
        return FR_NO_FILESYSTEM; /* No FAT volume is found */

    /* An FAT volume is found. Following code initializes the file system object */

    if (LD_WORD(fs->win+BPB_BytsPerSec) != SS(fs)) /* (BPB_BytsPerSec must be equal to the physical sector size) */
        return FR_NO_FILESYSTEM;

    fasize = LD_WORD(fs->win+BPB_FATSz16); /* Number of sectors per FAT */
    if (!fasize)
        fasize = LD_DWORD(fs->win+BPB_FATSz32);
    fs->fsize = fasize;

    fs->n_fats = b = fs->win[BPB_NumFATs]; /* Number of FAT copies */
    if (b != 1 && b != 2)
        return FR_NO_FILESYSTEM; /* (Must be 1 or 2) */
    fasize *= b; /* Number of sectors for FAT area */

    fs->csize = b = fs->win[BPB_SecPerClus]; /* Number of sectors per cluster */
    if (!b || (b & (b - 1)))
        return FR_NO_FILESYSTEM; /* (Must be power of 2) */

    fs->n_rootdir = LD_WORD(fs->win+BPB_RootEntCnt); /* Number of root directory entries */
    if (fs->n_rootdir % (SS(fs) / SZ_DIR))
        return FR_NO_FILESYSTEM; /* (BPB_RootEntCnt must be sector aligned) */

    tsect = LD_WORD(fs->win+BPB_TotSec16); /* Number of sectors on the volume */
    if (!tsect)
        tsect = LD_DWORD(fs->win+BPB_TotSec32);

    nrsv = LD_WORD(fs->win+BPB_RsvdSecCnt); /* Number of reserved sectors */
    if (!nrsv)
        return FR_NO_FILESYSTEM; /* (BPB_RsvdSecCnt must not be 0) */

    /* Determine the FAT sub type */
    sysect = nrsv + fasize + fs->n_rootdir / (SS(fs) / SZ_DIR); /* RSV+FAT+DIR */
    if (tsect < sysect)
        return FR_NO_FILESYSTEM; /* (Invalid volume size) */
    nclst = (tsect - sysect) / fs->csize; /* Number of clusters */
    if (!nclst)
        return FR_NO_FILESYSTEM; /* (Invalid volume size) */
    fmt = FS_FAT12;
    if (nclst >= MIN_FAT16)
        fmt = FS_FAT16;
    if (nclst >= MIN_FAT32)
        fmt = FS_FAT32;

    /* Boundaries and Limits */
    fs->n_fatent = nclst + 2; /* Number of FAT entries */
    fs->volbase = bsect; /* Volume start sector */
    fs->fatbase = bsect + nrsv; /* FAT start sector */
    fs->database = bsect + sysect; /* Data start sector */
    if (fmt == FS_FAT32) {
        if (fs->n_rootdir)
            return FR_NO_FILESYSTEM; /* (BPB_RootEntCnt must be 0) */
        fs->dirbase = LD_DWORD(fs->win+BPB_RootClus); /* Root directory start cluster */
        szbfat = fs->n_fatent * 4; /* (Required FAT size) */
    } else {
        if (!fs->n_rootdir)
            return FR_NO_FILESYSTEM; /* (BPB_RootEntCnt must not be 0) */
        fs->dirbase = fs->fatbase + fasize; /* Root directory start sector */
        szbfat = (fmt == FS_FAT16) ? /* (Required FAT size) */
        fs->n_fatent * 2 : fs->n_fatent * 3 / 2 + (fs->n_fatent & 1);
    }
    if (fs->fsize < (szbfat + (SS(fs) - 1)) / SS(fs)) /* (BPB_FATSz must not be less than required) */
        return FR_NO_FILESYSTEM;

#if !_FS_READONLY
    /* Initialize cluster allocation information */
    fs->free_clust = 0xFFFFFFFF;
    fs->last_clust = 0;

    /* Get fsinfo if available */
    if (fmt == FS_FAT32) {
        fs->fsi_flag = 0;
        fs->fsi_sector = bsect + LD_WORD(fs->win+BPB_FSInfo);
        if (disk_read(fs->drv, fs->win, fs->fsi_sector, 1) == RES_OK && LD_WORD(fs->win+BS_55AA) == 0xAA55
                && LD_DWORD(fs->win+FSI_LeadSig) == 0x41615252 && LD_DWORD(fs->win+FSI_StrucSig) == 0x61417272) {
            fs->last_clust = LD_DWORD(fs->win+FSI_Nxt_Free);
            fs->free_clust = LD_DWORD(fs->win+FSI_Free_Count);
        }
    }
#endif
    fs->fs_type = fmt; /* FAT sub-type */
    fs->id = ++Fsid; /* File system mount ID */
    fs->winsect = 0; /* Invalidate sector cache */
    fs->wflag = 0;
#if _FS_RPATH
    fs->cdir = 0; /* Current directory (root dir) */
#endif
#if _FS_LOCK				/* Clear file lock semaphores */
    clear_lock(fs);
#endif

    return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Check if the file/dir object is valid or not                          */
/*-----------------------------------------------------------------------*/

static FRESULT validate( /* FR_OK(0): The object is valid, !=0: Invalid */
void* obj /* Pointer to the object FIL/DIR to check validity */
) {
    FIL *fil = (FIL*) obj; /* Assuming offset of fs and id in the FIL/DIR is identical */

    if (!fil || !fil->fs || !fil->fs->fs_type || fil->fs->id != fil->id)
        return FR_INVALID_OBJECT;

    ENTER_FF(fil->fs); /* Lock file system */

    if (disk_status(fil->fs->drv) & STA_NOINIT)
        return FR_NOT_READY;

    return FR_OK;
}

/*--------------------------------------------------------------------------

 Public Functions

 --------------------------------------------------------------------------*/

/*-----------------------------------------------------------------------*/
/* Mount/Unmount a Logical Drive                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_mount(BYTE vol, /* Logical drive number to be mounted/unmounted */
FATFS *fs /* Pointer to new file system object (NULL for unmount)*/
) {
    FATFS *rfs;

    if (vol >= _VOLUMES) /* Check if the drive number is valid */
        return FR_INVALID_DRIVE;
    rfs = FatFs[vol]; /* Get current fs object */

    if (rfs) {
#if _FS_LOCK
        clear_lock(rfs);
#endif
#if _FS_REENTRANT				/* Discard sync object of the current volume */
        if (!ff_del_syncobj(rfs->sobj)) return FR_INT_ERR;
#endif
        rfs->fs_type = 0; /* Clear old fs object */
    }

    if (fs) {
        fs->fs_type = 0; /* Clear new fs object */
#if _FS_REENTRANT				/* Create sync object for the new volume */
        if (!ff_cre_syncobj(vol, &fs->sobj)) return FR_INT_ERR;
#endif
    }
    FatFs[vol] = fs; /* Register new fs object */

    return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Open or Create a File                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_open(FIL *fp, /* Pointer to the blank file object */
const TCHAR *path, /* Pointer to the file name */
BYTE mode /* Access mode and file open mode flags */
) {
    FRESULT res;
    DIR dj;
    BYTE *dir;
    DEF_NAMEBUF;

    if (!fp)
        return FR_INVALID_OBJECT;
    fp->fs = 0; /* Clear file object */

#if !_FS_READONLY
    mode &= FA_READ | FA_WRITE | FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW;
    res = chk_mounted(&path, &dj.fs, (BYTE) (mode & ~FA_READ));
#else
    mode &= FA_READ;
    res = chk_mounted(&path, &dj.fs, 0);
#endif
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        dir = dj.dir;
#if !_FS_READONLY	/* R/W configuration */
        if (res == FR_OK) {
            if (!dir) /* Current dir itself */
                res = FR_INVALID_NAME;
#if _FS_LOCK
            else
            res = chk_lock(&dj, (mode & ~FA_READ) ? 1 : 0);
#endif
        }
        /* Create or Open a file */
        if (mode & (FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW)) {
            DWORD dw, cl;

            if (res != FR_OK) { /* No file, create new */
                if (res == FR_NO_FILE) /* There is no file to open, create a new entry */
#if _FS_LOCK
                    res = enq_lock() ? dir_register(&dj) : FR_TOO_MANY_OPEN_FILES;
#else
                    res = dir_register(&dj);
#endif
                mode |= FA_CREATE_ALWAYS; /* File is created */
                dir = dj.dir; /* New entry */
            } else { /* Any object is already existing */
                if (dir[DIR_Attr] & (AM_RDO | AM_DIR)) { /* Cannot overwrite it (R/O or DIR) */
                    res = FR_DENIED;
                } else {
                    if (mode & FA_CREATE_NEW) /* Cannot create as new file */
                        res = FR_EXIST;
                }
            }
            if (res == FR_OK && (mode & FA_CREATE_ALWAYS)) { /* Truncate it if overwrite mode */
                dw = get_fattime(); /* Created time */
                ST_DWORD(dir+DIR_CrtTime, dw);
                dir[DIR_Attr] = 0; /* Reset attribute */
                ST_DWORD(dir+DIR_FileSize, 0); /* size = 0 */
                cl = ld_clust(dj.fs, dir); /* Get start cluster */
                st_clust(dir, 0); /* cluster = 0 */
                dj.fs->wflag = 1;
                if (cl) { /* Remove the cluster chain if exist */
                    dw = dj.fs->winsect;
                    res = remove_chain(dj.fs, cl);
                    if (res == FR_OK) {
                        dj.fs->last_clust = cl - 1; /* Reuse the cluster hole */
                        res = move_window(dj.fs, dw);
                    }
                }
            }
        } else { /* Open an existing file */
            if (res == FR_OK) { /* Follow succeeded */
                if (dir[DIR_Attr] & AM_DIR) { /* It is a directory */
                    res = FR_NO_FILE;
                } else {
                    if ((mode & FA_WRITE) && (dir[DIR_Attr] & AM_RDO)) /* R/O violation */
                        res = FR_DENIED;
                }
            }
        }
        if (res == FR_OK) {
            if (mode & FA_CREATE_ALWAYS) /* Set file change flag if created or overwritten */
                mode |= FA__WRITTEN;
            fp->dir_sect = dj.fs->winsect; /* Pointer to the directory entry */
            fp->dir_ptr = dir;
#if _FS_LOCK
            fp->lockid = inc_lock(&dj, (mode & ~FA_READ) ? 1 : 0);
            if (!fp->lockid) res = FR_INT_ERR;
#endif
        }

#else				/* R/O configuration */
        if (res == FR_OK) { /* Follow succeeded */
            dir = dj.dir;
            if (!dir) { /* Current dir itself */
                res = FR_INVALID_NAME;
            } else {
                if (dir[DIR_Attr] & AM_DIR) /* It is a directory */
                res = FR_NO_FILE;
            }
        }
#endif
        FREE_BUF();

        if (res == FR_OK) {
            fp->flag = mode; /* File access mode */
            fp->sclust = ld_clust(dj.fs, dir); /* File start cluster */
            fp->fsize = LD_DWORD(dir+DIR_FileSize); /* File size */
            fp->fptr = 0; /* File pointer */
            fp->dsect = 0;
#if _USE_FASTSEEK
            fp->cltbl = 0; /* Normal seek mode */
#endif
            fp->fs = dj.fs;
            fp->id = dj.fs->id; /* Validate file object */
        }
    }

    LEAVE_FF(dj.fs, res);
}

/*-----------------------------------------------------------------------*/
/* Read File                                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_read(FIL *fp, /* Pointer to the file object */
void *buff, /* Pointer to data buffer */
UINT btr, /* Number of bytes to read */
UINT *br /* Pointer to number of bytes read */
) {
    FRESULT res;
    DWORD clst, sect, remain;
    UINT rcnt, cc;
    BYTE csect, *rbuff = (BYTE*) buff;

    *br = 0; /* Clear read byte counter */

    res = validate(fp); /* Check validity */
    if (res != FR_OK)
        LEAVE_FF(fp->fs, res);
    if (fp->flag & FA__ERROR) /* Aborted file? */
        LEAVE_FF(fp->fs, FR_INT_ERR);
    if (!(fp->flag & FA_READ)) /* Check access mode */
        LEAVE_FF(fp->fs, FR_DENIED);
    remain = fp->fsize - fp->fptr;
    if (btr > remain)
        btr = (UINT) remain; /* Truncate btr by remaining bytes */

    for (; btr; /* Repeat until all data read */
    rbuff += rcnt, fp->fptr += rcnt, *br += rcnt, btr -= rcnt) {
        if ((fp->fptr % SS(fp->fs)) == 0) { /* On the sector boundary? */
            csect = (BYTE) (fp->fptr / SS(fp->fs) & (fp->fs->csize - 1)); /* Sector offset in the cluster */
            if (!csect) { /* On the cluster boundary? */
                if (fp->fptr == 0) { /* On the top of the file? */
                    clst = fp->sclust; /* Follow from the origin */
                } else { /* Middle or end of the file */
#if _USE_FASTSEEK
                    if (fp->cltbl)
                    clst = clmt_clust(fp, fp->fptr); /* Get cluster# from the CLMT */
                    else
#endif
                    clst = get_fat(fp->fs, fp->clust); /* Follow cluster chain on the FAT */
                }
                if (clst < 2)
                    ABORT(fp->fs, FR_INT_ERR);
                if (clst == 0xFFFFFFFF)
                    ABORT(fp->fs, FR_DISK_ERR);
                fp->clust = clst; /* Update current cluster */
            }
            sect = clust2sect(fp->fs, fp->clust); /* Get current sector */
            if (!sect)
                ABORT(fp->fs, FR_INT_ERR);
            sect += csect;
            cc = btr / SS(fp->fs); /* When remaining bytes >= sector size, */
            if (cc) { /* Read maximum contiguous sectors directly */
                if (csect + cc > fp->fs->csize) /* Clip at cluster boundary */
                    cc = fp->fs->csize - csect;
                if (disk_read(fp->fs->drv, rbuff, sect, (BYTE) cc) != RES_OK)
                    ABORT(fp->fs, FR_DISK_ERR);
#if !_FS_READONLY && _FS_MINIMIZE <= 2			/* Replace one of the read sectors with cached data if it contains a dirty sector */
#if _FS_TINY
                if (fp->fs->wflag && fp->fs->winsect - sect < cc)
                mem_cpy(rbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), fp->fs->win, SS(fp->fs));
#else
                if ((fp->flag & FA__DIRTY) && fp->dsect - sect < cc)
                    mem_cpy(rbuff + ((fp->dsect - sect) * SS(fp->fs)), fp->buf, SS(fp->fs));
#endif
#endif
                rcnt = SS(fp->fs) * cc; /* Number of bytes transferred */
                continue;
            }
#if !_FS_TINY
            if (fp->dsect != sect) { /* Load data sector if not in cache */
#if !_FS_READONLY
                if (fp->flag & FA__DIRTY) { /* Write-back dirty sector cache */
                    if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
                        ABORT(fp->fs, FR_DISK_ERR);
                    fp->flag &= ~FA__DIRTY;
                }
#endif
                if (disk_read(fp->fs->drv, fp->buf, sect, 1) != RES_OK) /* Fill sector cache */
                    ABORT(fp->fs, FR_DISK_ERR);
            }
#endif
            fp->dsect = sect;
        }
        rcnt = SS(fp->fs) - ((UINT) fp->fptr % SS(fp->fs)); /* Get partial sector data from sector buffer */
        if (rcnt > btr)
            rcnt = btr;
#if _FS_TINY
        if (move_window(fp->fs, fp->dsect)) /* Move sector window */
        ABORT(fp->fs, FR_DISK_ERR);
        mem_cpy(rbuff, &fp->fs->win[fp->fptr % SS(fp->fs)], rcnt); /* Pick partial sector */
#else
        mem_cpy(rbuff, &fp->buf[fp->fptr % SS(fp->fs)], rcnt); /* Pick partial sector */
#endif
    }

    LEAVE_FF(fp->fs, FR_OK);
}

#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Write File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_write(FIL *fp, /* Pointer to the file object */
const void *buff, /* Pointer to the data to be written */
UINT btw, /* Number of bytes to write */
UINT *bw /* Pointer to number of bytes written */
) {
    FRESULT res;
    DWORD clst, sect;
    UINT wcnt, cc;
    const BYTE *wbuff = (const BYTE*) buff;
    BYTE csect;

    *bw = 0; /* Clear write byte counter */

    res = validate(fp); /* Check validity */
    if (res != FR_OK)
        LEAVE_FF(fp->fs, res);
    if (fp->flag & FA__ERROR) /* Aborted file? */
        LEAVE_FF(fp->fs, FR_INT_ERR);
    if (!(fp->flag & FA_WRITE)) /* Check access mode */
        LEAVE_FF(fp->fs, FR_DENIED);
    if ((DWORD) (fp->fsize + btw) < fp->fsize)
        btw = 0; /* File size cannot reach 4GB */

    for (; btw; /* Repeat until all data written */
    wbuff += wcnt, fp->fptr += wcnt, *bw += wcnt, btw -= wcnt) {
        if ((fp->fptr % SS(fp->fs)) == 0) { /* On the sector boundary? */
            csect = (BYTE) (fp->fptr / SS(fp->fs) & (fp->fs->csize - 1)); /* Sector offset in the cluster */
            if (!csect) { /* On the cluster boundary? */
                if (fp->fptr == 0) { /* On the top of the file? */
                    clst = fp->sclust; /* Follow from the origin */
                    if (clst == 0) /* When no cluster is allocated, */
                        fp->sclust = clst = create_chain(fp->fs, 0); /* Create a new cluster chain */
                } else { /* Middle or end of the file */
#if _USE_FASTSEEK
                    if (fp->cltbl)
                    clst = clmt_clust(fp, fp->fptr); /* Get cluster# from the CLMT */
                    else
#endif
                    clst = create_chain(fp->fs, fp->clust); /* Follow or stretch cluster chain on the FAT */
                }
                if (clst == 0)
                    break; /* Could not allocate a new cluster (disk full) */
                if (clst == 1)
                    ABORT(fp->fs, FR_INT_ERR);
                if (clst == 0xFFFFFFFF)
                    ABORT(fp->fs, FR_DISK_ERR);
                fp->clust = clst; /* Update current cluster */
            }
#if _FS_TINY
            if (fp->fs->winsect == fp->dsect && sync_window(fp->fs)) /* Write-back sector cache */
            ABORT(fp->fs, FR_DISK_ERR);
#else
            if (fp->flag & FA__DIRTY) { /* Write-back sector cache */
                if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
                    ABORT(fp->fs, FR_DISK_ERR);
                fp->flag &= ~FA__DIRTY;
            }
#endif
            sect = clust2sect(fp->fs, fp->clust); /* Get current sector */
            if (!sect)
                ABORT(fp->fs, FR_INT_ERR);
            sect += csect;
            cc = btw / SS(fp->fs); /* When remaining bytes >= sector size, */
            if (cc) { /* Write maximum contiguous sectors directly */
                if (csect + cc > fp->fs->csize) /* Clip at cluster boundary */
                    cc = fp->fs->csize - csect;
                if (disk_write(fp->fs->drv, wbuff, sect, (BYTE) cc) != RES_OK)
                    ABORT(fp->fs, FR_DISK_ERR);
#if _FS_TINY
                if (fp->fs->winsect - sect < cc) { /* Refill sector cache if it gets invalidated by the direct write */
                    mem_cpy(fp->fs->win, wbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), SS(fp->fs));
                    fp->fs->wflag = 0;
                }
#else
                if (fp->dsect - sect < cc) { /* Refill sector cache if it gets invalidated by the direct write */
                    mem_cpy(fp->buf, wbuff + ((fp->dsect - sect) * SS(fp->fs)), SS(fp->fs));
                    fp->flag &= ~FA__DIRTY;
                }
#endif
                wcnt = SS(fp->fs) * cc; /* Number of bytes transferred */
                continue;
            }
#if _FS_TINY
            if (fp->fptr >= fp->fsize) { /* Avoid silly cache filling at growing edge */
                if (sync_window(fp->fs)) ABORT(fp->fs, FR_DISK_ERR);
                fp->fs->winsect = sect;
            }
#else
            if (fp->dsect != sect) { /* Fill sector cache with file data */
                if (fp->fptr < fp->fsize && disk_read(fp->fs->drv, fp->buf, sect, 1) != RES_OK)
                    ABORT(fp->fs, FR_DISK_ERR);
            }
#endif
            fp->dsect = sect;
        }
        wcnt = SS(fp->fs) - ((UINT) fp->fptr % SS(fp->fs));/* Put partial sector into file I/O buffer */
        if (wcnt > btw)
            wcnt = btw;
#if _FS_TINY
        if (move_window(fp->fs, fp->dsect)) /* Move sector window */
        ABORT(fp->fs, FR_DISK_ERR);
        mem_cpy(&fp->fs->win[fp->fptr % SS(fp->fs)], wbuff, wcnt); /* Fit partial sector */
        fp->fs->wflag = 1;
#else
        mem_cpy(&fp->buf[fp->fptr % SS(fp->fs)], wbuff, wcnt); /* Fit partial sector */
        fp->flag |= FA__DIRTY;
#endif
    }

    if (fp->fptr > fp->fsize)
        fp->fsize = fp->fptr; /* Update file size if needed */
    fp->flag |= FA__WRITTEN; /* Set file change flag */

    LEAVE_FF(fp->fs, FR_OK);
}

/*-----------------------------------------------------------------------*/
/* Synchronize the File Object                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_sync(FIL *fp /* Pointer to the file object */
) {
    FRESULT res;
    DWORD tm;
    BYTE *dir;

    res = validate(fp); /* Check validity of the object */
    if (res == FR_OK) {
        if (fp->flag & FA__WRITTEN) { /* Has the file been written? */
#if !_FS_TINY	/* Write-back dirty buffer */
            if (fp->flag & FA__DIRTY) {
                if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
                    LEAVE_FF(fp->fs, FR_DISK_ERR);
                fp->flag &= ~FA__DIRTY;
            }
#endif
            /* Update the directory entry */
            res = move_window(fp->fs, fp->dir_sect);
            if (res == FR_OK) {
                dir = fp->dir_ptr;
                dir[DIR_Attr] |= AM_ARC; /* Set archive bit */
                ST_DWORD(dir+DIR_FileSize, fp->fsize); /* Update file size */
                st_clust(dir, fp->sclust); /* Update start cluster */
                tm = get_fattime(); /* Update updated time */
                ST_DWORD(dir+DIR_WrtTime, tm);
                ST_WORD(dir+DIR_LstAccDate, 0);
                fp->flag &= ~FA__WRITTEN;
                fp->fs->wflag = 1;
                res = sync_fs(fp->fs);
            }
        }
    }

    LEAVE_FF(fp->fs, res);
}

#endif /* !_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* Close File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_close(FIL *fp /* Pointer to the file object to be closed */
) {
    FRESULT res;

#if _FS_READONLY
    res = validate(fp);
    {
#if _FS_REENTRANT
        FATFS *fs = fp->fs;
#endif
        if (res == FR_OK) fp->fs = 0; /* Discard file object */
        LEAVE_FF(fs, res);
    }
#else
    res = f_sync(fp); /* Flush cached data */
#if _FS_LOCK
    if (res == FR_OK) { /* Decrement open counter */
#if _FS_REENTRANT
        FATFS *fs = fp->fs;;
        res = validate(fp);
        if (res == FR_OK) {
            res = dec_lock(fp->lockid);
            unlock_fs(fs, FR_OK);
        }
#else
        res = dec_lock(fp->lockid);
#endif
    }
#endif
    if (res == FR_OK)
        fp->fs = 0; /* Discard file object */
    return res;
#endif
}

/*-----------------------------------------------------------------------*/
/* Current Drive/Directory Handlings                                     */
/*-----------------------------------------------------------------------*/

#if _FS_RPATH >= 1

FRESULT f_chdrive (
        BYTE drv /* Drive number */
)
{
    if (drv >= _VOLUMES) return FR_INVALID_DRIVE;

    CurrVol = drv;

    return FR_OK;
}

FRESULT f_chdir (
        const TCHAR *path /* Pointer to the directory path */
)
{
    FRESULT res;
    DIR dj;
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 0);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the path */
        FREE_BUF();
        if (res == FR_OK) { /* Follow completed */
            if (!dj.dir) {
                dj.fs->cdir = dj.sclust; /* Start directory itself */
            } else {
                if (dj.dir[DIR_Attr] & AM_DIR) /* Reached to the directory */
                dj.fs->cdir = ld_clust(dj.fs, dj.dir);
                else
                res = FR_NO_PATH; /* Reached but a file */
            }
        }
        if (res == FR_NO_FILE) res = FR_NO_PATH;
    }

    LEAVE_FF(dj.fs, res);
}

#if _FS_RPATH >= 2
FRESULT f_getcwd (
        TCHAR *buff, /* Pointer to the directory path */
        UINT len /* Size of path */
)
{
    FRESULT res;
    DIR dj;
    UINT i, n;
    DWORD ccl;
    TCHAR *tp;
    FILINFO fno;
    DEF_NAMEBUF;

    *buff = 0;
    res = chk_mounted((const TCHAR**)&buff, &dj.fs, 0); /* Get current volume */
    if (res == FR_OK) {
        INIT_BUF(dj);
        i = len; /* Bottom of buffer (dir stack base) */
        dj.sclust = dj.fs->cdir; /* Start to follow upper dir from current dir */
        while ((ccl = dj.sclust) != 0) { /* Repeat while current dir is a sub-dir */
            res = dir_sdi(&dj, 1); /* Get parent dir */
            if (res != FR_OK) break;
            res = dir_read(&dj, 0);
            if (res != FR_OK) break;
            dj.sclust = ld_clust(dj.fs, dj.dir); /* Goto parent dir */
            res = dir_sdi(&dj, 0);
            if (res != FR_OK) break;
            do { /* Find the entry links to the child dir */
                res = dir_read(&dj, 0);
                if (res != FR_OK) break;
                if (ccl == ld_clust(dj.fs, dj.dir)) break; /* Found the entry */
                res = dir_next(&dj, 0);
            }while (res == FR_OK);
            if (res == FR_NO_FILE) res = FR_INT_ERR;/* It cannot be 'not found'. */
            if (res != FR_OK) break;
#if _USE_LFN
            fno.lfname = buff;
            fno.lfsize = i;
#endif
            get_fileinfo(&dj, &fno); /* Get the dir name and push it to the buffer */
            tp = fno.fname;
            if (_USE_LFN && *buff) tp = buff;
            for (n = 0; tp[n]; n++);
            if (i < n + 3) {
                res = FR_NOT_ENOUGH_CORE; break;
            }
            while (n) buff[--i] = tp[--n];
            buff[--i] = '/';
        }
        tp = buff;
        if (res == FR_OK) {
            *tp++ = '0' + CurrVol; /* Put drive number */
            *tp++ = ':';
            if (i == len) { /* Root-dir */
                *tp++ = '/';
            } else { /* Sub-dir */
                do /* Add stacked path str */
                *tp++ = buff[i++];
                while (i < len);
            }
        }
        *tp = 0;
        FREE_BUF();
    }

    LEAVE_FF(dj.fs, res);
}
#endif /* _FS_RPATH >= 2 */
#endif /* _FS_RPATH >= 1 */

#if _FS_MINIMIZE <= 2
/*-----------------------------------------------------------------------*/
/* Seek File R/W Pointer                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_lseek(FIL *fp, /* Pointer to the file object */
DWORD ofs /* File pointer from top of file */
) {
    FRESULT res;

    res = validate(fp); /* Check validity of the object */
    if (res != FR_OK)
        LEAVE_FF(fp->fs, res);
    if (fp->flag & FA__ERROR) /* Check abort flag */
        LEAVE_FF(fp->fs, FR_INT_ERR);

#if _USE_FASTSEEK
    if (fp->cltbl) { /* Fast seek */
        DWORD cl, pcl, ncl, tcl, dsc, tlen, ulen, *tbl;

        if (ofs == CREATE_LINKMAP) { /* Create CLMT */
            tbl = fp->cltbl;
            tlen = *tbl++; ulen = 2; /* Given table size and required table size */
            cl = fp->sclust; /* Top of the chain */
            if (cl) {
                do {
                    /* Get a fragment */
                    tcl = cl; ncl = 0; ulen += 2; /* Top, length and used items */
                    do {
                        pcl = cl; ncl++;
                        cl = get_fat(fp->fs, cl);
                        if (cl <= 1) ABORT(fp->fs, FR_INT_ERR);
                        if (cl == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
                    }while (cl == pcl + 1);
                    if (ulen <= tlen) { /* Store the length and top of the fragment */
                        *tbl++ = ncl; *tbl++ = tcl;
                    }
                }while (cl < fp->fs->n_fatent); /* Repeat until end of chain */
            }
            *fp->cltbl = ulen; /* Number of items used */
            if (ulen <= tlen)
            *tbl = 0; /* Terminate table */
            else
            res = FR_NOT_ENOUGH_CORE; /* Given table size is smaller than required */

        } else { /* Fast seek */
            if (ofs > fp->fsize) /* Clip offset at the file size */
            ofs = fp->fsize;
            fp->fptr = ofs; /* Set file pointer */
            if (ofs) {
                fp->clust = clmt_clust(fp, ofs - 1);
                dsc = clust2sect(fp->fs, fp->clust);
                if (!dsc) ABORT(fp->fs, FR_INT_ERR);
                dsc += (ofs - 1) / SS(fp->fs) & (fp->fs->csize - 1);
                if (fp->fptr % SS(fp->fs) && dsc != fp->dsect) { /* Refill sector cache if needed */
#if !_FS_TINY
#if !_FS_READONLY
                    if (fp->flag & FA__DIRTY) { /* Write-back dirty sector cache */
                        if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
                        ABORT(fp->fs, FR_DISK_ERR);
                        fp->flag &= ~FA__DIRTY;
                    }
#endif
                    if (disk_read(fp->fs->drv, fp->buf, dsc, 1) != RES_OK) /* Load current sector */
                    ABORT(fp->fs, FR_DISK_ERR);
#endif
                    fp->dsect = dsc;
                }
            }
        }
    } else
#endif

    /* Normal Seek */
    {
        DWORD clst, bcs, nsect, ifptr;

        if (ofs > fp->fsize /* In read-only mode, clip offset with the file size */
#if !_FS_READONLY
                && !(fp->flag & FA_WRITE)
#endif
                )
            ofs = fp->fsize;

        ifptr = fp->fptr;
        fp->fptr = nsect = 0;
        if (ofs) {
            bcs = (DWORD) fp->fs->csize * SS(fp->fs); /* Cluster size (byte) */
            if (ifptr > 0 && (ofs - 1) / bcs >= (ifptr - 1) / bcs) { /* When seek to same or following cluster, */
                fp->fptr = (ifptr - 1) & ~(bcs - 1); /* start from the current cluster */
                ofs -= fp->fptr;
                clst = fp->clust;
            } else { /* When seek to back cluster, */
                clst = fp->sclust; /* start from the first cluster */
#if !_FS_READONLY
                if (clst == 0) { /* If no cluster chain, create a new chain */
                    clst = create_chain(fp->fs, 0);
                    if (clst == 1)
                        ABORT(fp->fs, FR_INT_ERR);
                    if (clst == 0xFFFFFFFF)
                        ABORT(fp->fs, FR_DISK_ERR);
                    fp->sclust = clst;
                }
#endif
                fp->clust = clst;
            }
            if (clst != 0) {
                while (ofs > bcs) { /* Cluster following loop */
#if !_FS_READONLY
                    if (fp->flag & FA_WRITE) { /* Check if in write mode or not */
                        clst = create_chain(fp->fs, clst); /* Force stretch if in write mode */
                        if (clst == 0) { /* When disk gets full, clip file size */
                            ofs = bcs;
                            break;
                        }
                    } else
#endif
                        clst = get_fat(fp->fs, clst); /* Follow cluster chain if not in write mode */
                    if (clst == 0xFFFFFFFF)
                        ABORT(fp->fs, FR_DISK_ERR);
                    if (clst <= 1 || clst >= fp->fs->n_fatent)
                        ABORT(fp->fs, FR_INT_ERR);
                    fp->clust = clst;
                    fp->fptr += bcs;
                    ofs -= bcs;
                }
                fp->fptr += ofs;
                if (ofs % SS(fp->fs)) {
                    nsect = clust2sect(fp->fs, clst); /* Current sector */
                    if (!nsect)
                        ABORT(fp->fs, FR_INT_ERR);
                    nsect += ofs / SS(fp->fs);
                }
            }
        }
        if (fp->fptr % SS(fp->fs) && nsect != fp->dsect) { /* Fill sector cache if needed */
#if !_FS_TINY
#if !_FS_READONLY
            if (fp->flag & FA__DIRTY) { /* Write-back dirty sector cache */
                if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
                    ABORT(fp->fs, FR_DISK_ERR);
                fp->flag &= ~FA__DIRTY;
            }
#endif
            if (disk_read(fp->fs->drv, fp->buf, nsect, 1) != RES_OK) /* Fill sector cache */
                ABORT(fp->fs, FR_DISK_ERR);
#endif
            fp->dsect = nsect;
        }
#if !_FS_READONLY
        if (fp->fptr > fp->fsize) { /* Set file change flag if the file size is extended */
            fp->fsize = fp->fptr;
            fp->flag |= FA__WRITTEN;
        }
#endif
    }

    LEAVE_FF(fp->fs, res);
}

#if _FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Create a Directory Object                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_opendir(DIR *dj, /* Pointer to directory object to create */
const TCHAR *path /* Pointer to the directory path */
) {
    FRESULT res;
    FATFS *fs;
    DEF_NAMEBUF;

    if (!dj)
        return FR_INVALID_OBJECT;

    res = chk_mounted(&path, &dj->fs, 0);
    fs = dj->fs;
    if (res == FR_OK) {
        INIT_BUF(*dj);
        res = follow_path(dj, path); /* Follow the path to the directory */
        FREE_BUF();
        if (res == FR_OK) { /* Follow completed */
            if (dj->dir) { /* It is not the root dir */
                if (dj->dir[DIR_Attr] & AM_DIR) { /* The object is a directory */
                    dj->sclust = ld_clust(fs, dj->dir);
                } else { /* The object is not a directory */
                    res = FR_NO_PATH;
                }
            }
            if (res == FR_OK) {
                dj->id = fs->id;
                res = dir_sdi(dj, 0); /* Rewind dir */
            }
        }
        if (res == FR_NO_FILE)
            res = FR_NO_PATH;
        if (res != FR_OK)
            dj->fs = 0; /* Invalidate the dir object if function faild */
    } else {
        dj->fs = 0;
    }

    LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Read Directory Entry in Sequence                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_readdir(DIR *dj, /* Pointer to the open directory object */
FILINFO *fno /* Pointer to file information to return */
) {
    FRESULT res;
    DEF_NAMEBUF;

    res = validate(dj); /* Check validity of the object */
    if (res == FR_OK) {
        if (!fno) {
            res = dir_sdi(dj, 0); /* Rewind the directory object */
        } else {
            INIT_BUF(*dj);
            res = dir_read(dj, 0); /* Read an item */
            if (res == FR_NO_FILE) { /* Reached end of dir */
                dj->sect = 0;
                res = FR_OK;
            }
            if (res == FR_OK) { /* A valid entry is found */
                get_fileinfo(dj, fno); /* Get the object information */
                res = dir_next(dj, 0); /* Increment index for next */
                if (res == FR_NO_FILE) {
                    dj->sect = 0;
                    res = FR_OK;
                }
            } FREE_BUF();
        }
    }

    LEAVE_FF(dj->fs, res);
}

#if _FS_MINIMIZE == 0
/*-----------------------------------------------------------------------*/
/* Get File Status                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_stat(const TCHAR *path, /* Pointer to the file path */
FILINFO *fno /* Pointer to file information to return */
) {
    FRESULT res;
    DIR dj;
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 0);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        if (res == FR_OK) { /* Follow completed */
            if (dj.dir) /* Found an object */
                get_fileinfo(&dj, fno);
            else
                /* It is root dir */
                res = FR_INVALID_NAME;
        } FREE_BUF();
    }

    LEAVE_FF(dj.fs, res);
}

#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Get Number of Free Clusters                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_getfree(const TCHAR *path, /* Path name of the logical drive number */
DWORD *nclst, /* Pointer to a variable to return number of free clusters */
FATFS **fatfs /* Pointer to return pointer to corresponding file system object */
) {
    FRESULT res;
    FATFS *fs;
    DWORD n, clst, sect, stat;
    UINT i;
    BYTE fat, *p;

    /* Get drive number */
    res = chk_mounted(&path, fatfs, 0);
    fs = *fatfs;
    if (res == FR_OK) {
        /* If free_clust is valid, return it without full cluster scan */
        if (fs->free_clust <= fs->n_fatent - 2) {
            *nclst = fs->free_clust;
        } else {
            /* Get number of free clusters */
            fat = fs->fs_type;
            n = 0;
            if (fat == FS_FAT12) {
                clst = 2;
                do {
                    stat = get_fat(fs, clst);
                    if (stat == 0xFFFFFFFF) {
                        res = FR_DISK_ERR;
                        break;
                    }
                    if (stat == 1) {
                        res = FR_INT_ERR;
                        break;
                    }
                    if (stat == 0)
                        n++;
                } while (++clst < fs->n_fatent);
            } else {
                clst = fs->n_fatent;
                sect = fs->fatbase;
                i = 0;
                p = 0;
                do {
                    if (!i) {
                        res = move_window(fs, sect++);
                        if (res != FR_OK)
                            break;
                        p = fs->win;
                        i = SS(fs);
                    }
                    if (fat == FS_FAT16) {
                        if (LD_WORD(p) == 0)
                            n++;
                        p += 2;
                        i -= 2;
                    } else {
                        if ((LD_DWORD(p) & 0x0FFFFFFF) == 0)
                            n++;
                        p += 4;
                        i -= 4;
                    }
                } while (--clst);
            }
            fs->free_clust = n;
            if (fat == FS_FAT32)
                fs->fsi_flag = 1;
            *nclst = n;
        }
    }
    LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Truncate File                                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_truncate(FIL *fp /* Pointer to the file object */
) {
    FRESULT res;
    DWORD ncl;

    res = validate(fp); /* Check validity of the object */
    if (res == FR_OK) {
        if (fp->flag & FA__ERROR) { /* Check abort flag */
            res = FR_INT_ERR;
        } else {
            if (!(fp->flag & FA_WRITE)) /* Check access mode */
                res = FR_DENIED;
        }
    }
    if (res == FR_OK) {
        if (fp->fsize > fp->fptr) {
            fp->fsize = fp->fptr; /* Set file size to current R/W point */
            fp->flag |= FA__WRITTEN;
            if (fp->fptr == 0) { /* When set file size to zero, remove entire cluster chain */
                res = remove_chain(fp->fs, fp->sclust);
                fp->sclust = 0;
            } else { /* When truncate a part of the file, remove remaining clusters */
                ncl = get_fat(fp->fs, fp->clust);
                res = FR_OK;
                if (ncl == 0xFFFFFFFF)
                    res = FR_DISK_ERR;
                if (ncl == 1)
                    res = FR_INT_ERR;
                if (res == FR_OK && ncl < fp->fs->n_fatent) {
                    res = put_fat(fp->fs, fp->clust, 0x0FFFFFFF);
                    if (res == FR_OK)
                        res = remove_chain(fp->fs, ncl);
                }
            }
        }
        if (res != FR_OK)
            fp->flag |= FA__ERROR;
    }

    LEAVE_FF(fp->fs, res);
}

/*-----------------------------------------------------------------------*/
/* Delete a File or Directory                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_unlink(const TCHAR *path /* Pointer to the file or directory path */
) {
    FRESULT res;
    DIR dj, sdj;
    BYTE *dir;
    DWORD dclst;
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME; /* Cannot remove dot entry */
#if _FS_LOCK
        if (res == FR_OK) res = chk_lock(&dj, 2); /* Cannot remove open file */
#endif
        if (res == FR_OK) { /* The object is accessible */
            dir = dj.dir;
            if (!dir) {
                res = FR_INVALID_NAME; /* Cannot remove the start directory */
            } else {
                if (dir[DIR_Attr] & AM_RDO)
                    res = FR_DENIED; /* Cannot remove R/O object */
            }
            dclst = ld_clust(dj.fs, dir);
            if (res == FR_OK && (dir[DIR_Attr] & AM_DIR)) { /* Is it a sub-dir? */
                if (dclst < 2) {
                    res = FR_INT_ERR;
                } else {
                    mem_cpy(&sdj, &dj, sizeof(DIR)); /* Check if the sub-dir is empty or not */
                    sdj.sclust = dclst;
                    res = dir_sdi(&sdj, 2); /* Exclude dot entries */
                    if (res == FR_OK) {
                        res = dir_read(&sdj, 0); /* Read an item */
                        if (res == FR_OK /* Not empty dir */
#if _FS_RPATH
                                || dclst == dj.fs->cdir /* Current dir */
#endif
                                )
                            res = FR_DENIED;
                        if (res == FR_NO_FILE)
                            res = FR_OK; /* Empty */
                    }
                }
            }
            if (res == FR_OK) {
                res = dir_remove(&dj); /* Remove the directory entry */
                if (res == FR_OK) {
                    if (dclst) /* Remove the cluster chain if exist */
                        res = remove_chain(dj.fs, dclst);
                    if (res == FR_OK)
                        res = sync_fs(dj.fs);
                }
            }
        } FREE_BUF();
    }

    LEAVE_FF(dj.fs, res);
}

/*-----------------------------------------------------------------------*/
/* Create a Directory                                                    */
/*-----------------------------------------------------------------------*/

FRESULT f_mkdir(const TCHAR *path /* Pointer to the directory path */
) {
    FRESULT res;
    DIR dj;
    BYTE *dir, n;
    DWORD dsc, dcl, pcl, tm = get_fattime();
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        if (res == FR_OK)
            res = FR_EXIST; /* Any object with same name is already existing */
        if (_FS_RPATH && res == FR_NO_FILE && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
        if (res == FR_NO_FILE) { /* Can create a new directory */
            dcl = create_chain(dj.fs, 0); /* Allocate a cluster for the new directory table */
            res = FR_OK;
            if (dcl == 0)
                res = FR_DENIED; /* No space to allocate a new cluster */
            if (dcl == 1)
                res = FR_INT_ERR;
            if (dcl == 0xFFFFFFFF)
                res = FR_DISK_ERR;
            if (res == FR_OK) /* Flush FAT */
                res = sync_window(dj.fs);
            if (res == FR_OK) { /* Initialize the new directory table */
                dsc = clust2sect(dj.fs, dcl);
                dir = dj.fs->win;
                mem_set(dir, 0, SS(dj.fs));
                mem_set(dir + DIR_Name, ' ', 11); /* Create "." entry */
                dir[DIR_Name] = '.';
                dir[DIR_Attr] = AM_DIR;
                ST_DWORD(dir+DIR_WrtTime, tm);
                st_clust(dir, dcl);
                mem_cpy(dir + SZ_DIR, dir, SZ_DIR); /* Create ".." entry */
                dir[33] = '.';
                pcl = dj.sclust;
                if (dj.fs->fs_type == FS_FAT32 && pcl == dj.fs->dirbase)
                    pcl = 0;
                st_clust(dir + SZ_DIR, pcl);
                for (n = dj.fs->csize; n; n--) { /* Write dot entries and clear following sectors */
                    dj.fs->winsect = dsc++;
                    dj.fs->wflag = 1;
                    res = sync_window(dj.fs);
                    if (res != FR_OK)
                        break;
                    mem_set(dir, 0, SS(dj.fs));
                }
            }
            if (res == FR_OK)
                res = dir_register(&dj); /* Register the object to the directoy */
            if (res != FR_OK) {
                remove_chain(dj.fs, dcl); /* Could not register, remove cluster chain */
            } else {
                dir = dj.dir;
                dir[DIR_Attr] = AM_DIR; /* Attribute */
                ST_DWORD(dir+DIR_WrtTime, tm); /* Created time */
                st_clust(dir, dcl); /* Table start cluster */
                dj.fs->wflag = 1;
                res = sync_fs(dj.fs);
            }
        } FREE_BUF();
    }

    LEAVE_FF(dj.fs, res);
}

/*-----------------------------------------------------------------------*/
/* Change Attribute                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_chmod(const TCHAR *path, /* Pointer to the file path */
BYTE value, /* Attribute bits */
BYTE mask /* Attribute mask to change */
) {
    FRESULT res;
    DIR dj;
    BYTE *dir;
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        FREE_BUF();
        if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
        if (res == FR_OK) {
            dir = dj.dir;
            if (!dir) { /* Is it a root directory? */
                res = FR_INVALID_NAME;
            } else { /* File or sub directory */
                mask &= AM_RDO | AM_HID | AM_SYS | AM_ARC; /* Valid attribute mask */
                dir[DIR_Attr] = (value & mask) | (dir[DIR_Attr] & (BYTE) ~mask); /* Apply attribute change */
                dj.fs->wflag = 1;
                res = sync_fs(dj.fs);
            }
        }
    }

    LEAVE_FF(dj.fs, res);
}

/*-----------------------------------------------------------------------*/
/* Change Timestamp                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_utime(const TCHAR *path, /* Pointer to the file/directory name */
const FILINFO *fno /* Pointer to the time stamp to be set */
) {
    FRESULT res;
    DIR dj;
    BYTE *dir;
    DEF_NAMEBUF;

    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path); /* Follow the file path */
        FREE_BUF();
        if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
        if (res == FR_OK) {
            dir = dj.dir;
            if (!dir) { /* Root directory */
                res = FR_INVALID_NAME;
            } else { /* File or sub-directory */
                ST_WORD(dir+DIR_WrtTime, fno->ftime);
                ST_WORD(dir+DIR_WrtDate, fno->fdate);
                dj.fs->wflag = 1;
                res = sync_fs(dj.fs);
            }
        }
    }

    LEAVE_FF(dj.fs, res);
}

/*-----------------------------------------------------------------------*/
/* Rename File/Directory                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_rename(const TCHAR *path_old, /* Pointer to the old name */
const TCHAR *path_new /* Pointer to the new name */
) {
    FRESULT res;
    DIR djo, djn;
    BYTE buf[21], *dir;
    DWORD dw;
    DEF_NAMEBUF;

    res = chk_mounted(&path_old, &djo.fs, 1);
    if (res == FR_OK) {
        djn.fs = djo.fs;
        INIT_BUF(djo);
        res = follow_path(&djo, path_old); /* Check old object */
        if (_FS_RPATH && res == FR_OK && (djo.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
#if _FS_LOCK
        if (res == FR_OK) res = chk_lock(&djo, 2);
#endif
        if (res == FR_OK) { /* Old object is found */
            if (!djo.dir) { /* Is root dir? */
                res = FR_NO_FILE;
            } else {
                mem_cpy(buf, djo.dir + DIR_Attr, 21); /* Save the object information except for name */
                mem_cpy(&djn, &djo, sizeof(DIR)); /* Check new object */
                res = follow_path(&djn, path_new);
                if (res == FR_OK)
                    res = FR_EXIST; /* The new object name is already existing */
                if (res == FR_NO_FILE) { /* Is it a valid path and no name collision? */
                    /* Start critical section that any interruption can cause a cross-link */
                    res = dir_register(&djn); /* Register the new entry */
                    if (res == FR_OK) {
                        dir = djn.dir; /* Copy object information except for name */
                        mem_cpy(dir + 13, buf + 2, 19);
                        dir[DIR_Attr] = buf[0] | AM_ARC;
                        djo.fs->wflag = 1;
                        if (djo.sclust != djn.sclust && (dir[DIR_Attr] & AM_DIR)) { /* Update .. entry in the directory if needed */
                            dw = clust2sect(djo.fs, ld_clust(djo.fs, dir));
                            if (!dw) {
                                res = FR_INT_ERR;
                            } else {
                                res = move_window(djo.fs, dw);
                                dir = djo.fs->win + SZ_DIR; /* .. entry */
                                if (res == FR_OK && dir[1] == '.') {
                                    dw = (djo.fs->fs_type == FS_FAT32 && djn.sclust == djo.fs->dirbase) ? 0 : djn.sclust;
                                    st_clust(dir, dw);
                                    djo.fs->wflag = 1;
                                }
                            }
                        }
                        if (res == FR_OK) {
                            res = dir_remove(&djo); /* Remove old entry */
                            if (res == FR_OK)
                                res = sync_fs(djo.fs);
                        }
                    }
                    /* End critical section */
                }
            }
        } FREE_BUF();
    }

    LEAVE_FF(djo.fs, res);
}

#endif /* !_FS_READONLY */
#endif /* _FS_MINIMIZE == 0 */
#endif /* _FS_MINIMIZE <= 1 */
#endif /* _FS_MINIMIZE <= 2 */

#if _USE_LABEL
/*-----------------------------------------------------------------------*/
/* Get volume label                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_getlabel (
        const TCHAR* path, /* Path name of the logical drive number */
        TCHAR* label, /* Pointer to a buffer to return the volume label */
        DWORD* sn /* Pointer to a variable to return the volume serial number */
)
{
    FRESULT res;
    DIR dj;
    UINT i, j;

    /* Get logical drive */
    res = chk_mounted(&path, &dj.fs, 0);

    /* Get volume label */
    if (res == FR_OK && label) {
        dj.sclust = 0; /* Open root dir */
        res = dir_sdi(&dj, 0);
        if (res == FR_OK) {
            res = dir_read(&dj, 1); /* Get an entry with AM_VOL */
            if (res == FR_OK) { /* A volume label is exist */
#if _LFN_UNICODE
                WCHAR w;
                i = j = 0;
                do {
                    w = (i < 11) ? dj.dir[i++] : ' ';
                    if (IsDBCS1(w) && i < 11 && IsDBCS2(dj.dir[i]))
                    w = (w << 8) | dj.dir[i++];
                    label[j++] = ff_convert(w, 1);
                }while (j < 11);
#else
                mem_cpy(label, dj.dir, 11);
#endif
                j = 11;
                do {
                    label[j] = 0;
                    if (!j) break;
                }while (label[--j] == ' ');
            }
            if (res == FR_NO_FILE) { /* No label, return nul string */
                label[0] = 0;
                res = FR_OK;
            }
        }
    }

    /* Get volume serial number */
    if (res == FR_OK && sn) {
        res = move_window(dj.fs, dj.fs->volbase);
        if (res == FR_OK) {
            i = dj.fs->fs_type == FS_FAT32 ? BS_VolID32 : BS_VolID;
            *sn = LD_DWORD(&dj.fs->win[i]);
        }
    }

    LEAVE_FF(dj.fs, res);
}

#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Set volume label                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_setlabel (
        const TCHAR* label /* Pointer to the volume label to set */
)
{
    FRESULT res;
    DIR dj;
    BYTE vn[11];
    UINT i, j, sl;
    WCHAR w;
    DWORD tm;

    /* Get logical drive */
    res = chk_mounted(&label, &dj.fs, 1);
    if (res) LEAVE_FF(dj.fs, res);

    /* Create a volume label in directory form */
    vn[0] = 0;
    for (sl = 0; label[sl]; sl++); /* Get name length */
    for (; sl && label[sl-1] == ' '; sl--); /* Remove trailing spaces */
    if (sl) { /* Create volume label in directory form */
        i = j = 0;
        do {
#if _LFN_UNICODE
            w = ff_convert(ff_wtoupper(label[i++]), 0);
#else
            w = (BYTE)label[i++];
            if (IsDBCS1(w))
            w = (j < 10 && i < sl && IsDBCS2(label[i])) ? (w << 8) | (BYTE)label[i++] : 0;
#if _USE_LFN
            w = ff_convert(ff_wtoupper(ff_convert(w, 1)), 0);
#else
            if (IsLower(w)) w -= 0x20; /* To upper ASCII chars */
#ifdef _EXCVT
            if (w >= 0x80) w = ExCvt[w - 0x80]; /* To upper extended chars (SBCS cfg) */
#else
            if (!_DF1S && w >= 0x80) w = 0; /* Reject extended chars (ASCII cfg) */
#endif
#endif
#endif
            if (!w || chk_chr("\"*+,.:;<=>\?[]|\x7F", w) || j >= (UINT)((w >= 0x100) ? 10 : 11)) /* Reject invalid chars for volume label */
            LEAVE_FF(dj.fs, FR_INVALID_NAME);
            if (w >= 0x100) vn[j++] = (BYTE)(w >> 8);
            vn[j++] = (BYTE)w;
        }while (i < sl);
        while (j < 11) vn[j++] = ' ';
    }

    /* Set volume label */
    dj.sclust = 0; /* Open root dir */
    res = dir_sdi(&dj, 0);
    if (res == FR_OK) {
        res = dir_read(&dj, 1); /* Get an entry with AM_VOL */
        if (res == FR_OK) { /* A volume label is found */
            if (vn[0]) {
                mem_cpy(dj.dir, vn, 11); /* Change the volume label name */
                tm = get_fattime();
                ST_DWORD(dj.dir+DIR_WrtTime, tm);
            } else {
                dj.dir[0] = DDE; /* Remove the volume label */
            }
            dj.fs->wflag = 1;
            res = sync_fs(dj.fs);
        } else { /* No volume label is found or error */
            if (res == FR_NO_FILE) {
                res = FR_OK;
                if (vn[0]) { /* Create volume label as new */
                    res = dir_alloc(&dj, 1); /* Allocate an entry for volume label */
                    if (res == FR_OK) {
                        mem_set(dj.dir, 0, SZ_DIR); /* Set volume label */
                        mem_cpy(dj.dir, vn, 11);
                        dj.dir[DIR_Attr] = AM_VOL;
                        tm = get_fattime();
                        ST_DWORD(dj.dir+DIR_WrtTime, tm);
                        dj.fs->wflag = 1;
                        res = sync_fs(dj.fs);
                    }
                }
            }
        }
    }

    LEAVE_FF(dj.fs, res);
}

#endif /* !_FS_READONLY */
#endif /* _USE_LABEL */

/*-----------------------------------------------------------------------*/
/* Forward data to the stream directly (available on only tiny cfg)      */
/*-----------------------------------------------------------------------*/
#if _USE_FORWARD && _FS_TINY

FRESULT f_forward (
        FIL *fp, /* Pointer to the file object */
        UINT (*func)(const BYTE*,UINT), /* Pointer to the streaming function */
        UINT btf, /* Number of bytes to forward */
        UINT *bf /* Pointer to number of bytes forwarded */
)
{
    FRESULT res;
    DWORD remain, clst, sect;
    UINT rcnt;
    BYTE csect;

    *bf = 0; /* Clear transfer byte counter */

    res = validate(fp); /* Check validity of the object */
    if (res != FR_OK) LEAVE_FF(fp->fs, res);
    if (fp->flag & FA__ERROR) /* Check error flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
    if (!(fp->flag & FA_READ)) /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);

    remain = fp->fsize - fp->fptr;
    if (btf > remain) btf = (UINT)remain; /* Truncate btf by remaining bytes */

    for (; btf && (*func)(0, 0); /* Repeat until all data transferred or stream becomes busy */
            fp->fptr += rcnt, *bf += rcnt, btf -= rcnt) {
        csect = (BYTE)(fp->fptr / SS(fp->fs) & (fp->fs->csize - 1)); /* Sector offset in the cluster */
        if ((fp->fptr % SS(fp->fs)) == 0) { /* On the sector boundary? */
            if (!csect) { /* On the cluster boundary? */
                clst = (fp->fptr == 0) ? /* On the top of the file? */
                fp->sclust : get_fat(fp->fs, fp->clust);
                if (clst <= 1) ABORT(fp->fs, FR_INT_ERR);
                if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
                fp->clust = clst; /* Update current cluster */
            }
        }
        sect = clust2sect(fp->fs, fp->clust); /* Get current data sector */
        if (!sect) ABORT(fp->fs, FR_INT_ERR);
        sect += csect;
        if (move_window(fp->fs, sect)) /* Move sector window */
        ABORT(fp->fs, FR_DISK_ERR);
        fp->dsect = sect;
        rcnt = SS(fp->fs) - (WORD)(fp->fptr % SS(fp->fs)); /* Forward data from sector window */
        if (rcnt > btf) rcnt = btf;
        rcnt = (*func)(&fp->fs->win[(WORD)fp->fptr % SS(fp->fs)], rcnt);
        if (!rcnt) ABORT(fp->fs, FR_INT_ERR);
    }

    LEAVE_FF(fp->fs, FR_OK);
}
#endif /* _USE_FORWARD */

#if _USE_MKFS && !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Create File System on the Drive                                       */
/*-----------------------------------------------------------------------*/
#define N_ROOTDIR	512		/* Number of root dir entries for FAT12/16 */
#define N_FATS		1		/* Number of FAT copies (1 or 2) */

FRESULT f_mkfs (
        BYTE vol, /* Logical drive number */
        BYTE sfd, /* Partitioning rule 0:FDISK, 1:SFD */
        UINT au /* Allocation unit size [bytes] */
)
{
    static const WORD vst[] = {1024, 512, 256, 128, 64, 32, 16, 8, 4, 2, 0};
    static const WORD cst[] = {32768, 16384, 8192, 4096, 2048, 16384, 8192, 4096, 2048, 1024, 512};
    BYTE fmt, md, sys, *tbl, pdrv, part;
    DWORD n_clst, vs, n, wsect;
    UINT i;
    DWORD b_vol, b_fat, b_dir, b_data; /* LBA */
    DWORD n_vol, n_rsv, n_fat, n_dir; /* Size */
    FATFS *fs;
    DSTATUS stat;

    /* Check mounted drive and clear work area */
    if (vol >= _VOLUMES) return FR_INVALID_DRIVE;
    if (sfd > 1) return FR_INVALID_PARAMETER;
    if (au & (au - 1)) return FR_INVALID_PARAMETER;
    fs = FatFs[vol];
    if (!fs) return FR_NOT_ENABLED;
    fs->fs_type = 0;
    pdrv = LD2PD(vol); /* Physical drive */
    part = LD2PT(vol); /* Partition (0:auto detect, 1-4:get from partition table)*/

    /* Get disk statics */
    stat = disk_initialize(pdrv);
    if (stat & STA_NOINIT) return FR_NOT_READY;
    if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;
#if _MAX_SS != 512					/* Get disk sector size */
    if (disk_ioctl(pdrv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK || SS(fs) > _MAX_SS)
    return FR_DISK_ERR;
#endif
    if (_MULTI_PARTITION && part) {
        /* Get partition information from partition table in the MBR */
        if (disk_read(pdrv, fs->win, 0, 1) != RES_OK) return FR_DISK_ERR;
        if (LD_WORD(fs->win+BS_55AA) != 0xAA55) return FR_MKFS_ABORTED;
        tbl = &fs->win[MBR_Table + (part - 1) * SZ_PTE];
        if (!tbl[4]) return FR_MKFS_ABORTED; /* No partition? */
        b_vol = LD_DWORD(tbl+8); /* Volume start sector */
        n_vol = LD_DWORD(tbl+12); /* Volume size */
    } else {
        /* Create a partition in this function */
        if (disk_ioctl(pdrv, GET_SECTOR_COUNT, &n_vol) != RES_OK || n_vol < 128)
        return FR_DISK_ERR;
        b_vol = (sfd) ? 0 : 63; /* Volume start sector */
        n_vol -= b_vol; /* Volume size */
    }

    if (!au) { /* AU auto selection */
        vs = n_vol / (2000 / (SS(fs) / 512));
        for (i = 0; vs < vst[i]; i++);
        au = cst[i];
    }
    au /= SS(fs); /* Number of sectors per cluster */
    if (au == 0) au = 1;
    if (au > 128) au = 128;

    /* Pre-compute number of clusters and FAT sub-type */
    n_clst = n_vol / au;
    fmt = FS_FAT12;
    if (n_clst >= MIN_FAT16) fmt = FS_FAT16;
    if (n_clst >= MIN_FAT32) fmt = FS_FAT32;

    /* Determine offset and size of FAT structure */
    if (fmt == FS_FAT32) {
        n_fat = ((n_clst * 4) + 8 + SS(fs) - 1) / SS(fs);
        n_rsv = 32;
        n_dir = 0;
    } else {
        n_fat = (fmt == FS_FAT12) ? (n_clst * 3 + 1) / 2 + 3 : (n_clst * 2) + 4;
        n_fat = (n_fat + SS(fs) - 1) / SS(fs);
        n_rsv = 1;
        n_dir = (DWORD)N_ROOTDIR * SZ_DIR / SS(fs);
    }
    b_fat = b_vol + n_rsv; /* FAT area start sector */
    b_dir = b_fat + n_fat * N_FATS; /* Directory area start sector */
    b_data = b_dir + n_dir; /* Data area start sector */
    if (n_vol < b_data + au - b_vol) return FR_MKFS_ABORTED; /* Too small volume */

    /* Align data start sector to erase block boundary (for flash memory media) */
    if (disk_ioctl(pdrv, GET_BLOCK_SIZE, &n) != RES_OK || !n || n > 32768) n = 1;
    n = (b_data + n - 1) & ~(n - 1); /* Next nearest erase block from current data start */
    n = (n - b_data) / N_FATS;
    if (fmt == FS_FAT32) { /* FAT32: Move FAT offset */
        n_rsv += n;
        b_fat += n;
    } else { /* FAT12/16: Expand FAT size */
        n_fat += n;
    }

    /* Determine number of clusters and final check of validity of the FAT sub-type */
    n_clst = (n_vol - n_rsv - n_fat * N_FATS - n_dir) / au;
    if ( (fmt == FS_FAT16 && n_clst < MIN_FAT16)
            || (fmt == FS_FAT32 && n_clst < MIN_FAT32))
    return FR_MKFS_ABORTED;

    switch (fmt) { /* Determine system ID for partition table */
        case FS_FAT12: sys = 0x01; break;
        case FS_FAT16: sys = (n_vol < 0x10000) ? 0x04 : 0x06; break;
        default: sys = 0x0C;
    }

    if (_MULTI_PARTITION && part) {
        /* Update system ID in the partition table */
        tbl = &fs->win[MBR_Table + (part - 1) * SZ_PTE];
        tbl[4] = sys;
        if (disk_write(pdrv, fs->win, 0, 1) != RES_OK) return FR_DISK_ERR;
        md = 0xF8;
    } else {
        if (sfd) { /* No partition table (SFD) */
            md = 0xF0;
        } else { /* Create partition table (FDISK) */
            mem_set(fs->win, 0, SS(fs));
            tbl = fs->win+MBR_Table; /* Create partition table for single partition in the drive */
            tbl[1] = 1; /* Partition start head */
            tbl[2] = 1; /* Partition start sector */
            tbl[3] = 0; /* Partition start cylinder */
            tbl[4] = sys; /* System type */
            tbl[5] = 254; /* Partition end head */
            n = (b_vol + n_vol) / 63 / 255;
            tbl[6] = (BYTE)((n >> 2) | 63); /* Partition end sector */
            tbl[7] = (BYTE)n; /* End cylinder */
            ST_DWORD(tbl+8, 63); /* Partition start in LBA */
            ST_DWORD(tbl+12, n_vol); /* Partition size in LBA */
            ST_WORD(fs->win+BS_55AA, 0xAA55); /* MBR signature */
            if (disk_write(pdrv, fs->win, 0, 1) != RES_OK) /* Write it to the MBR sector */
            return FR_DISK_ERR;
            md = 0xF8;
        }
    }

    /* Create BPB in the VBR */
    tbl = fs->win; /* Clear sector */
    mem_set(tbl, 0, SS(fs));
    mem_cpy(tbl, "\xEB\xFE\x90" "MSDOS5.0", 11);/* Boot jump code, OEM name */
    i = SS(fs); /* Sector size */
    ST_WORD(tbl+BPB_BytsPerSec, i);
    tbl[BPB_SecPerClus] = (BYTE)au; /* Sectors per cluster */
    ST_WORD(tbl+BPB_RsvdSecCnt, n_rsv); /* Reserved sectors */
    tbl[BPB_NumFATs] = N_FATS; /* Number of FATs */
    i = (fmt == FS_FAT32) ? 0 : N_ROOTDIR; /* Number of rootdir entries */
    ST_WORD(tbl+BPB_RootEntCnt, i);
    if (n_vol < 0x10000) { /* Number of total sectors */
        ST_WORD(tbl+BPB_TotSec16, n_vol);
    } else {
        ST_DWORD(tbl+BPB_TotSec32, n_vol);
    }
    tbl[BPB_Media] = md; /* Media descriptor */
    ST_WORD(tbl+BPB_SecPerTrk, 63); /* Number of sectors per track */
    ST_WORD(tbl+BPB_NumHeads, 255); /* Number of heads */
    ST_DWORD(tbl+BPB_HiddSec, b_vol); /* Hidden sectors */
    n = get_fattime(); /* Use current time as VSN */
    if (fmt == FS_FAT32) {
        ST_DWORD(tbl+BS_VolID32, n); /* VSN */
        ST_DWORD(tbl+BPB_FATSz32, n_fat); /* Number of sectors per FAT */
        ST_DWORD(tbl+BPB_RootClus, 2); /* Root directory start cluster (2) */
        ST_WORD(tbl+BPB_FSInfo, 1); /* FSInfo record offset (VBR+1) */
        ST_WORD(tbl+BPB_BkBootSec, 6); /* Backup boot record offset (VBR+6) */
        tbl[BS_DrvNum32] = 0x80; /* Drive number */
        tbl[BS_BootSig32] = 0x29; /* Extended boot signature */
        mem_cpy(tbl+BS_VolLab32, "NO NAME    " "FAT32   ", 19); /* Volume label, FAT signature */
    } else {
        ST_DWORD(tbl+BS_VolID, n); /* VSN */
        ST_WORD(tbl+BPB_FATSz16, n_fat); /* Number of sectors per FAT */
        tbl[BS_DrvNum] = 0x80; /* Drive number */
        tbl[BS_BootSig] = 0x29; /* Extended boot signature */
        mem_cpy(tbl+BS_VolLab, "NO NAME    " "FAT     ", 19); /* Volume label, FAT signature */
    }
    ST_WORD(tbl+BS_55AA, 0xAA55); /* Signature (Offset is fixed here regardless of sector size) */
    if (disk_write(pdrv, tbl, b_vol, 1) != RES_OK) /* Write it to the VBR sector */
    return FR_DISK_ERR;
    if (fmt == FS_FAT32) /* Write backup VBR if needed (VBR+6) */
    disk_write(pdrv, tbl, b_vol + 6, 1);

    /* Initialize FAT area */
    wsect = b_fat;
    for (i = 0; i < N_FATS; i++) { /* Initialize each FAT copy */
        mem_set(tbl, 0, SS(fs)); /* 1st sector of the FAT  */
        n = md; /* Media descriptor byte */
        if (fmt != FS_FAT32) {
            n |= (fmt == FS_FAT12) ? 0x00FFFF00 : 0xFFFFFF00;
            ST_DWORD(tbl+0, n); /* Reserve cluster #0-1 (FAT12/16) */
        } else {
            n |= 0xFFFFFF00;
            ST_DWORD(tbl+0, n); /* Reserve cluster #0-1 (FAT32) */
            ST_DWORD(tbl+4, 0xFFFFFFFF);
            ST_DWORD(tbl+8, 0x0FFFFFFF); /* Reserve cluster #2 for root dir */
        }
        if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
        return FR_DISK_ERR;
        mem_set(tbl, 0, SS(fs)); /* Fill following FAT entries with zero */
        for (n = 1; n < n_fat; n++) { /* This loop may take a time on FAT32 volume due to many single sector writes */
            if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
            return FR_DISK_ERR;
        }
    }

    /* Initialize root directory */
    i = (fmt == FS_FAT32) ? au : n_dir;
    do {
        if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
        return FR_DISK_ERR;
    }while (--i);

#if _USE_ERASE	/* Erase data area if needed */
    {
        DWORD eb[2];

        eb[0] = wsect; eb[1] = wsect + (n_clst - ((fmt == FS_FAT32) ? 1 : 0)) * au - 1;
        disk_ioctl(pdrv, CTRL_ERASE_SECTOR, eb);
    }
#endif

    /* Create FSInfo if needed */
    if (fmt == FS_FAT32) {
        ST_DWORD(tbl+FSI_LeadSig, 0x41615252);
        ST_DWORD(tbl+FSI_StrucSig, 0x61417272);
        ST_DWORD(tbl+FSI_Free_Count, n_clst - 1); /* Number of free clusters */
        ST_DWORD(tbl+FSI_Nxt_Free, 2); /* Last allocated cluster# */
        ST_WORD(tbl+BS_55AA, 0xAA55);
        disk_write(pdrv, tbl, b_vol + 1, 1); /* Write original (VBR+1) */
        disk_write(pdrv, tbl, b_vol + 7, 1); /* Write backup (VBR+7) */
    }

    return (disk_ioctl(pdrv, CTRL_SYNC, 0) == RES_OK) ? FR_OK : FR_DISK_ERR;
}

#if _MULTI_PARTITION
/*-----------------------------------------------------------------------*/
/* Divide Physical Drive                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_fdisk (
        BYTE pdrv, /* Physical drive number */
        const DWORD szt[], /* Pointer to the size table for each partitions */
        void* work /* Pointer to the working buffer */
)
{
    UINT i, n, sz_cyl, tot_cyl, b_cyl, e_cyl, p_cyl;
    BYTE s_hd, e_hd, *p, *buf = (BYTE*)work;
    DSTATUS stat;
    DWORD sz_disk, sz_part, s_part;

    stat = disk_initialize(pdrv);
    if (stat & STA_NOINIT) return FR_NOT_READY;
    if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;
    if (disk_ioctl(pdrv, GET_SECTOR_COUNT, &sz_disk)) return FR_DISK_ERR;

    /* Determine CHS in the table regardless of the drive geometry */
    for (n = 16; n < 256 && sz_disk / n / 63 > 1024; n *= 2);
    if (n == 256) n--;
    e_hd = n - 1;
    sz_cyl = 63 * n;
    tot_cyl = sz_disk / sz_cyl;

    /* Create partition table */
    mem_set(buf, 0, _MAX_SS);
    p = buf + MBR_Table; b_cyl = 0;
    for (i = 0; i < 4; i++, p += SZ_PTE) {
        p_cyl = (szt[i] <= 100) ? (DWORD)tot_cyl * szt[i] / 100 : szt[i] / sz_cyl;
        if (!p_cyl) continue;
        s_part = (DWORD)sz_cyl * b_cyl;
        sz_part = (DWORD)sz_cyl * p_cyl;
        if (i == 0) { /* Exclude first track of cylinder 0 */
            s_hd = 1;
            s_part += 63; sz_part -= 63;
        } else {
            s_hd = 0;
        }
        e_cyl = b_cyl + p_cyl - 1;
        if (e_cyl >= tot_cyl) return FR_INVALID_PARAMETER;

        /* Set partition table */
        p[1] = s_hd; /* Start head */
        p[2] = (BYTE)((b_cyl >> 2) + 1); /* Start sector */
        p[3] = (BYTE)b_cyl; /* Start cylinder */
        p[4] = 0x06; /* System type (temporary setting) */
        p[5] = e_hd; /* End head */
        p[6] = (BYTE)((e_cyl >> 2) + 63); /* End sector */
        p[7] = (BYTE)e_cyl; /* End cylinder */
        ST_DWORD(p + 8, s_part); /* Start sector in LBA */
        ST_DWORD(p + 12, sz_part); /* Partition size */

        /* Next partition */
        b_cyl += p_cyl;
    }
    ST_WORD(p, 0xAA55);

    /* Write it to the MBR */
    return (disk_write(pdrv, buf, 0, 1) || disk_ioctl(pdrv, CTRL_SYNC, 0)) ? FR_DISK_ERR : FR_OK;
}

#endif /* _MULTI_PARTITION */
#endif /* _USE_MKFS && !_FS_READONLY */

#if _USE_STRFUNC
/*-----------------------------------------------------------------------*/
/* Get a string from the file                                            */
/*-----------------------------------------------------------------------*/

TCHAR* f_gets (
        TCHAR* buff, /* Pointer to the string buffer to read */
        int len, /* Size of string buffer (characters) */
        FIL* fp /* Pointer to the file object */
)
{
    int n = 0;
    TCHAR c, *p = buff;
    BYTE s[2];
    UINT rc;

    while (n < len - 1) { /* Read bytes until buffer gets filled */
        f_read(fp, s, 1, &rc);
        if (rc != 1) break; /* Break on EOF or error */
        c = s[0];
#if _LFN_UNICODE					/* Read a character in UTF-8 encoding */
        if (c >= 0x80) {
            if (c < 0xC0) continue; /* Skip stray trailer */
            if (c < 0xE0) { /* Two-byte sequence */
                f_read(fp, s, 1, &rc);
                if (rc != 1) break;
                c = ((c & 0x1F) << 6) | (s[0] & 0x3F);
                if (c < 0x80) c = '?';
            } else {
                if (c < 0xF0) { /* Three-byte sequence */
                    f_read(fp, s, 2, &rc);
                    if (rc != 2) break;
                    c = (c << 12) | ((s[0] & 0x3F) << 6) | (s[1] & 0x3F);
                    if (c < 0x800) c = '?';
                } else { /* Reject four-byte sequence */
                    c = '?';
                }
            }
        }
#endif
#if _USE_STRFUNC >= 2
        if (c == '\r') continue; /* Strip '\r' */
#endif
        *p++ = c;
        n++;
        if (c == '\n') break; /* Break on EOL */
    }
    *p = 0;
    return n ? buff : 0; /* When no data read (eof or error), return with error. */
}

#if !_FS_READONLY
#include <stdarg.h>
/*-----------------------------------------------------------------------*/
/* Put a character to the file                                           */
/*-----------------------------------------------------------------------*/

int f_putc (
        TCHAR c, /* A character to be output */
        FIL* fp /* Pointer to the file object */
)
{
    UINT bw, btw;
    BYTE s[3];

#if _USE_STRFUNC >= 2
    if (c == '\n') f_putc ('\r', fp); /* LF -> CRLF conversion */
#endif

#if _LFN_UNICODE	/* Write the character in UTF-8 encoding */
    if (c < 0x80) { /* 7-bit */
        s[0] = (BYTE)c;
        btw = 1;
    } else {
        if (c < 0x800) { /* 11-bit */
            s[0] = (BYTE)(0xC0 | (c >> 6));
            s[1] = (BYTE)(0x80 | (c & 0x3F));
            btw = 2;
        } else { /* 16-bit */
            s[0] = (BYTE)(0xE0 | (c >> 12));
            s[1] = (BYTE)(0x80 | ((c >> 6) & 0x3F));
            s[2] = (BYTE)(0x80 | (c & 0x3F));
            btw = 3;
        }
    }
#else				/* Write the character without conversion */
    s[0] = (BYTE)c;
    btw = 1;
#endif
    f_write(fp, s, btw, &bw); /* Write the char to the file */
    return (bw == btw) ? 1 : EOF; /* Return the result */
}

/*-----------------------------------------------------------------------*/
/* Put a string to the file                                              */
/*-----------------------------------------------------------------------*/

int f_puts (
        const TCHAR* str, /* Pointer to the string to be output */
        FIL* fp /* Pointer to the file object */
)
{
    int n;

    for (n = 0; *str; str++, n++) {
        if (f_putc(*str, fp) == EOF) return EOF;
    }
    return n;
}

/*-----------------------------------------------------------------------*/
/* Put a formatted string to the file                                    */
/*-----------------------------------------------------------------------*/

int f_printf (
        FIL* fp, /* Pointer to the file object */
        const TCHAR* str, /* Pointer to the format string */
        ... /* Optional arguments... */
)
{
    va_list arp;
    BYTE f, r;
    UINT i, j, w;
    ULONG v;
    TCHAR c, d, s[16], *p;
    int res, chc, cc;

    va_start(arp, str);

    for (cc = res = 0; cc != EOF; res += cc) {
        c = *str++;
        if (c == 0) break; /* End of string */
        if (c != '%') { /* Non escape character */
            cc = f_putc(c, fp);
            if (cc != EOF) cc = 1;
            continue;
        }
        w = f = 0;
        c = *str++;
        if (c == '0') { /* Flag: '0' padding */
            f = 1; c = *str++;
        } else {
            if (c == '-') { /* Flag: left justified */
                f = 2; c = *str++;
            }
        }
        while (IsDigit(c)) { /* Precision */
            w = w * 10 + c - '0';
            c = *str++;
        }
        if (c == 'l' || c == 'L') { /* Prefix: Size is long int */
            f |= 4; c = *str++;
        }
        if (!c) break;
        d = c;
        if (IsLower(d)) d -= 0x20;
        switch (d) { /* Type is... */
            case 'S' : /* String */
            p = va_arg(arp, TCHAR*);
            for (j = 0; p[j]; j++);
            chc = 0;
            if (!(f & 2)) {
                while (j++ < w) chc += (cc = f_putc(' ', fp));
            }
            chc += (cc = f_puts(p, fp));
            while (j++ < w) chc += (cc = f_putc(' ', fp));
            if (cc != EOF) cc = chc;
            continue;
            case 'C' : /* Character */
            cc = f_putc((TCHAR)va_arg(arp, int), fp); continue;
            case 'B' : /* Binary */
            r = 2; break;
            case 'O' : /* Octal */
            r = 8; break;
            case 'D' : /* Signed decimal */
            case 'U' : /* Unsigned decimal */
            r = 10; break;
            case 'X' : /* Hexdecimal */
            r = 16; break;
            default: /* Unknown type (pass-through) */
            cc = f_putc(c, fp); continue;
        }

        /* Get an argument and put it in numeral */
        v = (f & 4) ? (ULONG)va_arg(arp, long) : ((d == 'D') ? (ULONG)(long)va_arg(arp, int) : (ULONG)va_arg(arp, unsigned int));
        if (d == 'D' && (v & 0x80000000)) {
            v = 0 - v;
            f |= 8;
        }
        i = 0;
        do {
            d = (TCHAR)(v % r); v /= r;
            if (d > 9) d += (c == 'x') ? 0x27 : 0x07;
            s[i++] = d + '0';
        }while (v && i < sizeof s / sizeof s[0]);
        if (f & 8) s[i++] = '-';
        j = i; d = (f & 1) ? '0' : ' ';
        chc = 0;
        while (!(f & 2) && j++ < w) chc += (cc = f_putc(d, fp));
        do chc += (cc = f_putc(s[--i], fp)); while(i);
        while (j++ < w) chc += (cc = f_putc(' ', fp));
        if (cc != EOF) cc = chc;
    }

    va_end(arp);
    return (cc == EOF) ? cc : res;
}

#endif /* !_FS_READONLY */
#endif /* _USE_STRFUNC */
